#include <bits/stdc++.h>

//    #include <boost/multiprecision/cpp_int.hpp>
 #define int long long
 #define inf  1000000007
 #define pa pair<int,int>
 #define ll long long
 #define pal pair<double,double>
 #define ppap pair<pa,int>
  #define PI 3.14159265358979323846
  #define paa pair<int,char>
  #define  mp make_pair
  #define  pb push_back
  #define EPS (1e-10)
                                          
    int dx[8]={0,1,0,-1,1,1,-1,-1};
    int dy[8]={1,0,-1,0,-1,1,1,-1};
                                            using namespace std;
                                   			class pa3{
                                            	public:
                                            	int x;
                                   				int y,z;
                                            	pa3(int x=0,int y=0,int z=0):x(x),y(y),z(z) {}
                                            	bool operator < (const pa3 &p) const{
                                            		if(x!=p.x) return x<p.x;
                                            		if(y!=p.y) return y<p.y;
                                            		 return z<p.z;
                                            		//return x != p.x ? x<p.x: y<p.y;
                                            	}
                                   				bool operator > (const pa3 &p) const{
                                            		if(x!=p.x) return x>p.x;
                                            		if(y!=p.y) return y>p.y;
                                            		 return z>p.z;
                                            		//return x != p.x ? x<p.x: y<p.y;
                                            	}
                                            	bool operator == (const pa3 &p) const{
                                            		return x==p.x && y==p.y && z==p.z;
                                            	}
                                            		bool operator != (const pa3 &p) const{
                                            			return !( x==p.x && y==p.y && z==p.z);
                                            	}
                                            
                                            };
                                            
                                            class pa4{
                                            	public:
                                            	int x;
                                            	int y,z,w;
                                            	pa4(int x=0,int y=0,int z=0,int w=0):x(x),y(y),z(z),w(w) {}
                                            	bool operator < (const pa4 &p) const{
                                            		if(x!=p.x) return x<p.x;
                                            		if(y!=p.y) return y<p.y;
                                            		if(z!=p.z)return z<p.z;
                                            		return w<p.w;
                                            		//return x != p.x ? x<p.x: y<p.y;
                                            	}
                                            	bool operator > (const pa4 &p) const{
                                            		if(x!=p.x) return x>p.x;
                                            		if(y!=p.y) return y>p.y;
                                            		if(z!=p.z)return z>p.z;
                                            		return w>p.w;
                                            		//return x != p.x ? x<p.x: y<p.y;
                                            	}
                                            	bool operator == (const pa4 &p) const{
                                            		return x==p.x && y==p.y && z==p.z &&w==p.w;
                                            	}
                                            		
                                            
                                            };
                                            class pa2{
                                            	public:
                                            	int x,y;
                                            	pa2(int x=0,int y=0):x(x),y(y) {}
                                            	pa2 operator + (pa2 p) {return pa2(x+p.x,y+p.y);}
                                            	pa2 operator - (pa2 p) {return pa2(x-p.x,y-p.y);}
                                            	bool operator < (const pa2 &p) const{
                                            		return y != p.y ? y<p.y: x<p.x;
                                            	}
                                            	bool operator > (const pa2 &p) const{
                                            		return x != p.x ? x<p.x: y<p.y;
                                            	}
                                            	bool operator == (const pa2 &p) const{
                                            		return abs(x-p.x)==0 && abs(y-p.y)==0;
                                            	}
                                            	bool operator != (const pa2 &p) const{
                                            		return !(abs(x-p.x)==0 && abs(y-p.y)==0);
                                            	}
                                            		
                                            
                                            };
                                        

                                            class Point{
                                            	public:
                                            	double x,y;
                                            	Point(double x=0,double y=0):x(x),y(y) {}
                                            	Point operator + (Point p) {return Point(x+p.x,y+p.y);}
                                            	Point operator - (Point p) {return Point(x-p.x,y-p.y);}
                                            	Point operator * (double a) {return Point(x*a,y*a);}
                                            	Point operator / (double a) {return Point(x/a,y/a);}
                                            	double absv() {return sqrt(norm());}
                                            	double norm() {return x*x+y*y;}
                                            	bool operator < (const Point &p) const{
                                            		return x != p.x ? x<p.x: y<p.y;
                                            	}
                                            	bool operator == (const Point &p) const{
                                            		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
                                            	}
                                            };
                                            typedef Point Vector;
                                     #define pl pair<int,pas>
                                            struct Segment{
                                            Point p1,p2;
                                            };
                                             double dot(Vector a,Vector b){
                                            	return a.x*b.x+a.y*b.y;
                                            }
                                            double cross(Vector a,Vector b){
                                            	return a.x*b.y-a.y*b.x;
                                            }
                                        
                bool parareru(Point a,Point b,Point c,Point d){
                //	if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;
                	return abs(cross(a-b,d-c))<EPS;
                }
                double distance_ls_p(Point a, Point b, Point c) {
                  if ( dot(b-a, c-a) < EPS ) return (c-a).absv();
                  if ( dot(a-b, c-b) < EPS ) return (c-b).absv();
                  return abs(cross(b-a, c-a)) / (b-a).absv();
                }
                bool is_intersected_ls(Segment a,Segment b) {
                	if(a.p1==b.p1||a.p2==b.p1||a.p1==b.p2||a.p2==b.p2) return false;
                	if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&&parareru((a.p2),(a.p1),(a.p1),(b.p1))){
                //		cout<<"sss"<<endl;
                		if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;
                		if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;
                		if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;
                		if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;
                		return false;
                	}
                  else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );
                }
                 
                double segment_dis(Segment a,Segment b){
                	if(is_intersected_ls(a,b))return 0;
                	double r=distance_ls_p(a.p1, a.p2, b.p1);
                	r=min(r,distance_ls_p(a.p1, a.p2, b.p2));
                	r=min(r,distance_ls_p(b.p1, b.p2, a.p2));
                	r=min(r,distance_ls_p(b.p1, b.p2, a.p1));
                	return r;
                }
                Point intersection_ls(Segment a, Segment b) {
                  Point ba = b.p2-b.p1;
                  double d1 = abs(cross(ba, a.p1-b.p1));
                  double d2 = abs(cross(ba, a.p2-b.p1));
                  double t = d1 / (d1 + d2);
                 
                  return a.p1 + (a.p2-a.p1) * t;
                }
                
                                string itos( int i ) {
                                ostringstream s ;
                                s << i ;
                                return s.str() ;
                                }
                                 
                                int gcd(int v,int b){
                                	if(v>b) return gcd(b,v);
                                	if(v==b) return b;
                                	if(b%v==0) return v;
                                	return gcd(v,b%v);
                                }
                 
                                double distans(double x1,double y1,double x2,double y2){
                                	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
                                	return sqrt(rr);
                                	
                                }
                                int mod;
int extgcd(int a, int b, int &x, int &y) {
    if (b == 0) {
        x = 1;
        y = 0;
        return a;
    }
    int d = extgcd(b, a%b, y, x);
    y -= a/b * x;
    return d;
}
pa operator+(const pa & l,const pa & r) {   
    return {l.first+r.first,l.second+r.second};                                    
}    
                                
                int pr[1200010];
                int inv[1200010];
                
                int beki(int wa,int rr,int warukazu){
                	if(rr==0) return 1%warukazu;
                	if(rr==1) return wa%warukazu;
                	wa%=warukazu;
                	if(rr%2==1) return ((ll)beki(wa,rr-1,warukazu)*(ll)wa)%warukazu;
                	ll zx=beki(wa,rr/2,warukazu);
                	return (zx*zx)%warukazu;
                }
    double bekid(double w,int r){
    	if(r==0) return 1.0;
    	if(r==1) return w;
    	if(r%2) return bekid(w,r-1)*w;
    	double f=bekid(w,r/2);
    	return f*f;
    }
                
    			int comb(int nn,int rr){
    				int r=pr[nn]*inv[rr];
    				r%=mod;
    				r*=inv[nn-rr];
    				r%=mod;
    				return r;
    			}
                
                void gya(int ert){
                	pr[0]=1;
                	for(int i=1;i<=ert;i++){
                		pr[i]=(pr[i-1]*i)%mod;
                	}
                	for(int i=0;i<=ert;i++) inv[i]=beki(pr[i],mod-2,mod);
                	
                }
                
              //   cin.tie(0);
    		//	ios::sync_with_stdio(false);
    			//priority_queue<pa3,vector<pa3>,greater<pa3>> pq;            
                 //sort(ve.begin(),ve.end(),greater<int>());
    //mt19937(clock_per_sec);
  //  mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count()) ;
	   
       
                               //----------------kokomade tenpure------------

int modinv(int r,int mo){// mod mo での r の逆数 ないときは-1
	// r*x +mo*r = 1
	
	int aa,bb;
	int gc=extgcd(r,mo,aa,bb);
	if(gc!=-1){
	//	cout<<-1<<endl;
	}
	if(gc!=1) return -1;
	aa%=mo;
	if(aa<0)aa+=mo;
	
	return aa;
}


int garner(vector<pa> vec,int MOD){
	// vec[i]: x % vec[i].first == vec[i].second
	// 0<= vec[i].second<vec[i].first
	
	// vec[i].first はどの2つも互いに素！！！！
		vec.pb({MOD,0});
	
	int siz=vec.size();
	
	vector<int> ruiseki(siz,1);
	vector<int> teisuu(siz,0);
	//cout<<siz<<endl;
	int val;
	for(int i=0;i<siz-1;i++){
		
		// (teisuu[i] + val*ruiseki[i]) % vec[i].first = vec[i].second
		
		 val= vec[i].second-teisuu[i];
		while(val<0) val+=vec[i].first;
		val%=vec[i].first;
		val*= modinv(ruiseki[i],vec[i].first);
		val%=vec[i].first;
	//	cout<<i<<" "<<val<<endl;
		
		for(int j=i+1;j<siz;j++){
			teisuu[j]+=ruiseki[j]*val%vec[j].first;
			teisuu[j]%=vec[j].first;
			
			ruiseki[j]*=vec[i].first;
			ruiseki[j]%=vec[j].first;
		}
	}
	return teisuu.back();
	
	
}

map<int,vector<pa>> ve;

int x[1020],y[1020];

void soin(int r,int id){
	int rr=r;
	for(int i=2;i*i<=r;i++)if(rr%i==0){
		int g=0;
		while(rr%i==0){
			rr/=i;
			g++;
		}
			ve[i].pb({g,id});
	}
	if(rr>1){
			ve[rr].pb({1,id});
	}
}

int rui(int n,int r){
	if(r==1) return n;
	if(r%2) return rui(n,r-1)*n;
	int y=rui(n,r/2);
	return y*y;
}

signed main(){

	  cin.tie(0);
   			ios::sync_with_stdio(false);


int n=3;
	cin>>n;
	for(int i=0;i<n;i++){
		cin>>x[i]>>y[i];
		soin(y[i],i);
	}
	
	for(auto it=ve.begin();it!=ve.end();it++){
		if(((it)->second).size()==1) continue;
		sort(((*it).second).begin(),((*it).second).end(),greater<pa>());
		int nn=((*it).second).size();
	//	cout<<(*it).first<<" "<<nn<<endl;
		for(int i=0;i<nn;i++){
	//		cout<<" "<<(*it).first<<" "<<((*it).second)[i].first<<" "<<((*it).second)[i].second<<endl;
		}
		for(int i=1;i<nn;i++){
//			cout<<x[((*it).second)[i-1].second]%rui((*it).first,((*it).second)[i].first)<<endl;
//			cout<<x[((*it).second)[i].second]%rui((*it).first,((*it).second)[i].first)<<endl;
			
			if(x[((*it).second)[i-1].second]%rui((*it).first,((*it).second)[i].first)!=x[((*it).second)[i].second]%rui((*it).first,((*it).second)[i].first)){
				cout<<-1<<endl;
				return 0;
			}
		}
		for(int i=1;i<nn;i++){
		//	cout<<(*it).first<<" "<<((*it).second)[i].second<<" "<<rui((*it).first,((*it).second)[i].first)<<endl;
			y[((*it).second)[i].second]/=rui((*it).first,((*it).second)[i].first);
			x[((*it).second)[i].second]%=y[((*it).second)[i].second];
		}
//		for(int i=0;i<n;i++)cout<<x[i]<<" "<<y[i]<<endl;
	}
//	cout<<n<<endl;
//	for(int i=0;i<n;i++)cout<<x[i]<<" "<<y[i]<<endl;
	
	vector<pa> ans;
	for(int i=0;i<n;i++){
			ans.pb({y[i],x[i]});
	}
	int ko=garner(ans,inf);
	
	if(ko==0){
		ko=1;
		for(int i=0;i<n;i++){
			ko*=y[i];
			ko%=inf;
		}
	}
	cout<<ko<<endl;
	
	return 0;
}