#define CP_BUNDLED_SOURCE
#ifndef CP_BUNDLE_HEADER_3840A09F237A779E
#define CP_BUNDLE_HEADER_3840A09F237A779E
#ifdef TEMPLATE
#else
#define TEMPLATE
# pragma GCC optimize("O3")
#include <iostream>
#include <iomanip>
#include <cstdio>
#include <string>
#include <cstring>
#include <vector>
#include <list>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <algorithm>
#include <numeric>
#include <cmath>
#include <climits>
#include <cassert>
#include <functional>
#include <iterator>
#include <utility>
#include <complex>
#include <bitset>
#include <chrono>
#include <random>
#include <limits>
#include <optional>
#include <variant>
#include <any>

#include <array>
#include <bit>
#include <compare>
#include <concepts>
#include <numbers>
#include <ranges>
#include <span>
#include <string_view>
#include <tuple>
#include <type_traits>
#include <version>
using namespace std;
using uint=unsigned;
using ll=long long;
using ull=unsigned long long;
using ld=long double;
using pii=pair<int,int>;
using pll=pair<ll,ll>;
using i128=__int128;
using u128=unsigned __int128;
template<class T>using vc=vector<T>;
template<class T>using vvc=vc<vc<T>>;
template<class T>using vvvc=vvc<vc<T>>;
template<class T>using smpq=priority_queue<T,vector<T>,greater<T>>;
template<class T>using bipq=priority_queue<T>;
#define rep(i,n) for(ll i=0;i<(ll)(n);i++)
#define REP(i,j,n) for(ll i=(j);i<(ll)(n);i++)
#define DREP(i,n,m) for(ll i=(n);i>=(m);i--)
#define drep(i,n) for(ll i=((n)-1);i>=0;i--)
#define rall(x) x.rbegin(),x.rend()
#define mp(...) make_pair(__VA_ARGS__)
#define pb push_back
#define fi first
#define se second
#define is insert
#define bg begin()
#define ed end()
#define all(x) x.begin(),x.end()
void scan(int&a) { cin >> a; }
void scan(ll&a) { cin >> a; }
void scan(string&a) { cin >> a; }
void scan(char&a) { cin >> a; }
void scan(uint&a) { cin >> a; }
void scan(ull&a) { cin >> a; }
void scan(bool&a) { cin >> a; }
void scan(ld&a){ cin>> a;}
template<class T> void scan(vector<T>&a) { for(auto&x:a) scan(x); }
void read() {}
template<class Head, class... Tail> void read(Head&head, Tail&... tail) { scan(head); read(tail...); }
#define INT(...) int __VA_ARGS__; read(__VA_ARGS__);
#define LL(...) ll __VA_ARGS__; read(__VA_ARGS__);
#define ULL(...) ull __VA_ARGS__; read(__VA_ARGS__);
#define STR(...) string __VA_ARGS__; read(__VA_ARGS__);
#define VC(type, name, ...) vector<type> name(__VA_ARGS__); read(name);
#define VVC(type, name, size, ...) vector<vector<type>> name(size, vector<type>(__VA_ARGS__)); read(name);
template<class T>void print(T a) { cout << a; }
template<class T> void print(vector<T>a) { for(int i=0;i<(int)a.size();i++){if(i)cout<<" ";print(a[i]);}cout<<endl;}
void PRT() { cout <<endl; return ; }
template<class T> void PRT(T a) { print(a); cout <<endl; return; }
template<class Head, class... Tail> void PRT(Head head, Tail ... tail) { print(head); cout << " "; PRT(tail...); return; }
template<class T,class F>
bool chmin(T &x, F y){
    if(x>y){
        x=y;
        return true;
    }
    return false;
}
template<class T, class F>
bool chmax(T &x, F y){
    if(x<y){
        x=y;
        return true;
    }
    return false;
}
template <typename T>
T floor(T a, T b) {
  return a / b - (a % b && (a ^ b) < 0);
}
template <typename T>
T ceil(T x, T y) {
  return floor(x + y - 1, y);
}
template <typename T>
T bmod(T x, T y) {
  return x - y * floor(x, y);
}
template <typename T>
pair<T, T> divmod(T x, T y) {
  T q = floor(x, y);
  return {q, x - q * y};
}
void YesNo(bool b){
    cout<<(b?"Yes":"No")<<endl;
}
void YESNO(bool b){
    cout<<(b?"YES":"NO")<<endl;
}
void AliceBob(bool b){
    cout<<(b?"Alice":"Bob")<<endl;
}
void TakahashiAoki(bool b){
    cout<<(b?"Takahashi":"Aoki")<<endl;
}
void Yes(){
    cout<<"Yes"<<endl;
}
void No(){
    cout<<"No"<<endl;
}
vc<int>stovi(const string&s,const string&S){
    vc<int>v(s.size());
    rep(i,s.size()){
        auto t=S.find(s[i]);
        assert(t!=string::npos);
        v[i]=t;
    }
    return v;
}
template<class T=ll>
T isqrt(T x){
    T F=sqrtl(x);
    while((F+1)*(F+1)<=x)F++;
    while(F*F>x)F--;
    return F;
}
template<class T>
vvc<T>trans(const vvc<T>&a){
    assert(a.size()&&a[0].size());
    vvc<T>b(a[0].size(),vc<T>(a.size()));
    rep(i,a.size())rep(j,a[0].size()){
        b[j][i]=a[i][j];
    }
    return b;
}
template<class T>
vc<string>trans(const vc<string>&a){
    assert(a.size()&&a[0].size());
    vc<string>b(a[0].size(),string(a.size(),0));
    rep(i,a.size())rep(j,a[0].size()){
        b[j][i]=a[i][j];
    }
    return b;
}
template<class T>
int popcount(T n){
    return __builtin_popcountll(n);
}
template<class T,class L=ll>
L sum(vc<T>&a){
    return accumulate(all(a),L(0));
}
template<class T>
vc<T>subset(T S){
    vc<T>ans;
    for(T x=S;x>0;x=(x-1)&S)ans.pb(x);
    ans.pb(0);
    return ans;
}
template<class T>
T max(vc<T>&a){
    return *max_element(all(a));
}
template<class T>
T min(vc<T>&a){
    return *min_element(all(a));
}
template<class T,class L=ll>
vc<L> presum(vc<T> &a){
    vc<L> ret(a.size()+1);
    rep(i,a.size())ret[i+1]=ret[i]+a[i];
    return ret;
}
template<class T, class F>
vc<T> &operator+=(vc<T> &a,F b){
    for (auto&v:a)v += b;
    return a;
}
template<class T, class F>
vc<T> &operator-=(vc<T>&a,F b){
    for (auto&v:a)v-=b;
    return a;
}
template<class T, class F>
vc<T> &operator*=(vc<T>&a,F b){
    for (auto&v:a)v*=b;
    return a;
}
template<class T=ll>
constexpr T pow(T a,T b){
    T res=1;
    while(b){
        if(b&1)res*=a;
        a*=a;
        b/=2;
    }
    return res;
}
constexpr ll ten(ll a){
    return pow<ll>(10,a);
}
template<typename T>constexpr T inf=numeric_limits<T>::max()/2-1;
template<class T>
int tbit(T x){
    using U=make_unsigned_t<T>;
    U y=(U)x;
    return y?(int)bit_width(y)-1:-1;
}
template<class T>
int lbit(T x){
    using U=make_unsigned_t<T>;
    U y=(U)x;
    return y?(int)countr_zero(y):-1;
}
template<class T>
int tbit(T x,int p){
    using U=make_unsigned_t<T>;
    constexpr int W=numeric_limits<U>::digits;
    U y=(U)x;
    if(p<0)return -1;
    if(p>=W-1)return tbit(y);
    return tbit(y&((U(1)<<(p+1))-1));
}
template<class T>
int lbit(T x,int p){
    using U=make_unsigned_t<T>;
    constexpr int W=numeric_limits<U>::digits;
    U y=(U)x;
    if(p<0)return lbit(y);
    if(p>=W)return -1;
    return lbit(y&(~U(0)<<p));
}
istream& operator>>(istream&is,i128&x){
    string s;is>>s;
    x=0;
    int i=0,neg=0;
    if(s[0]=='-')neg=1,i=1;
    for(;i<(int)s.size();i++)x=x*10+s[i]-'0';
    if(neg)x=-x;
    return is;
}
ostream& operator<<(ostream&os,i128 x){
    if(x==0)return os<<0;
    if(x<0)os<<"-";
    u128 y=x<0?-(u128)x:(u128)x;
    string s;
    while(y)s.pb('0'+y%10),y/=10;
    reverse(all(s));
    return os<<s;
}
#ifdef LOCAL
#include "debug/debug.hpp"
#else
#define dbg(...) ((void)0)
#endif

struct template_setup{
    template_setup(){
        #ifdef LOCAL
        freopen("input.txt","r",stdin);
        freopen("output.txt","w",stdout);
        
        #endif
        cin.tie(0)->sync_with_stdio(0);
        #ifdef LOCAL
        cout<<fixed<<setprecision(6);
        dbg("==============="s);
        #else
        cout<<fixed<<setprecision(20);
        #endif
    }
};
inline template_setup template_setup;

#if defined(LOCAL)&&!defined(CP_NO_AUTO_ALL)&&!defined(CP_BUNDLED_SOURCE)
#include <all.hpp>
#endif

#endif
#endif
#ifndef CP_BUNDLE_HEADER_01D6A785D0F4E280
#define CP_BUNDLE_HEADER_01D6A785D0F4E280

ull mod_mul(ull a,ull b,ull m){
    return ull(static_cast<u128>(a)*b%m);
}
template<class T>
T modpow(T a,T n,T m){
    T res=1%m;a%=m;
    while(n){
        if(n%2)res=res*a%m;
        a=a*a%m;
        n/=2;
    }
    return res;
}
int is_prime(ll n){
    if(n<=1)return 0;
    if(n==2)return 1;
    if(n%2==0)return 0;
    ll k=0,q=n-1;
    while(q%2==0){
        q/=2;
        k++;
    }
    auto judge=[&](vc<ll> base)->int{
        for(auto x:base){
            x%=n;
            if(x==0)continue;
            ll v=modpow<i128>(x,q,n);
            if(v!=1){
                rep(i,k){
                    if(v==n-1)goto end;
                    v=i128(v)*v%n;
                }
                return 0;
            }
            end:;
        }
        return 1;
    };
    if(n<4759123141LL){
        return judge({2,7,61});
    }else{
        return judge({2,325,9375,28178,450775,9780504,1795265022});
    }
}
ll pollard_rho(ll n){
    if(n%2==0)return 2;
    if(n%3==0)return 3;
    static mt19937_64 mt(random_device{}());
    while(1){
        ull y=mt()%(n-1)+1;
        ull c=mt()%(n-1)+1;
        auto f=[&](ull v){
            return (mod_mul(v,v,n)+c)%n;        };
        ull r=1,g=1,x=0,ys=0;
        const ull M=128;
        while(g==1){
            x=y;
            rep(i,r)y=f(y);
            for(ull k=0;k<r&&g==1;k+=M){
                ys=y;
                ull q=1;
                rep(i,min(M,r-k)){
                    y=f(y);
                    ull d=x>y?x-y:y-x;
                    q=mod_mul(q,d,n);
                }
                g=gcd(q,(ull)n);
            }
            r*=2;
        }
        if(g==n){
            do{
                ys=f(ys);
                ull d=x>ys?x-ys:ys-x;
                g=gcd(d,(ull)n);
            }while(g==1);
        }

        if(g!=n)return g;
    }
}
void inner_factorize(ll n,vc<ll>&facts){
    if(n==1)return;
    if(is_prime(n)){
        facts.pb(n);
        return;
    }
    ll d=pollard_rho(n);
    inner_factorize(d,facts);
    inner_factorize(n/d,facts);
}
vc<pair<ll,ll>>factorize(ll n){
    vc<ll> facts;
    inner_factorize(n,facts);
    sort(all(facts));
    vc<pair<ll,ll>> res;
    for(auto p:facts){
        if(res.empty()||res.back().first!=p){
            res.pb({p,1});
        }else{
            res.back().second++;
        }    
    }
    return res;
}

template<class T>
vc<T>divisors(T x){
    auto f=factorize(x);
    vc<T>res;
    auto dfs=[&](auto&dfs,int fr,T v){
        if(fr==f.size()){
            res.pb(v);
            return;
        }
        rep(i,f[fr].second+1){
            dfs(dfs,fr+1,v);
            v*=f[fr].fi;
        }
    };
    dfs(dfs,0,1);
    return res;
}
#endif
void solve(){
    LL(n,k);
    for(ll N=n;N>=1;N--){
        auto ps=divisors(N);
        int ok=1;
        for(auto&x:ps){
            ok&=!(x<=k&&N/x<=k);
        }
        if(ok){
            return PRT(N);
        }
        if(ps.size()==1)break;
    }
    return PRT(-1);
}
signed main(){
    int t=1;
     cin >> t;
    while(t--)solve();
}