#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define FORR2(x,y,arr) for(auto& [x,y]:arr)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
template<class T> bool chmax(T &a, const T &b) { if(a<b){a=b;return 1;}return 0;}
template<class T> bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;}
//-------------------------------------------------------

int T;
ll N,S;
const ll mo=998244353;

ll modpow(ll a, ll n=mo-2) {
	ll r=1;
	while(n) r=r*((n%2)?a:1)%mo,a=a*a%mo,n>>=1;
	return r;
}

map<ll,ll> memo[101];

ll comb(ll P_,ll Q_) {
	if(P_<0 || Q_<0 || Q_>P_) return 0;
	ll p=1,q=1;
	Q_=min(Q_,P_-Q_);
	if(memo[Q_].count(P_)==0) {
		P_%=mo;
		for(int i=1;i<=Q_;i++) p=p*P_%mo, q=q*i%mo,P_--;
		memo[Q_][P_]=p*modpow(q,mo-2)%mo;
	}
	
	return memo[Q_][P_];
}

ll hcomb(ll P_,ll Q_) { return (P_==0&&Q_==0)?1:comb(P_+Q_-1,Q_);}

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>T;
	while(T--) {
		cin>>N>>S;
		
		ll ret=1;
		for(i=2;i<=100;i++) {
			if(N%i==0) {
				x=0;
				while(N%i==0) {
					x++;
					N/=i;
				}
				
				ll pat=0;
				ll a=1;
				FOR(j,x+1) {
					(pat+=a*hcomb(S-1,x-j))%=mo;
					a=a*i;
				}
				ret=ret*pat%mo;
			}
			
		}
		ret=ret*(S%mo)%mo;
		cout<<ret<<endl;
	}
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}