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

#include<atcoder/all>
using namespace atcoder;
using mint = modint998244353;
vector<mint> fact, factinv, inv;
const ll mod = 998244353;
void prenCkModp(ll n) {
    fact.resize(n + 5);
    factinv.resize(n + 5);
    inv.resize(n + 5);
    fact[0] = fact[1] = 1;
    factinv[0] = factinv[1] = 1;
    inv[1] = 1;
    for (ll i = 2; i < n + 5; i++) {
        fact[i] = (fact[i - 1] * i);
        inv[i] = mod - (inv[mod % i] * (mod / i));
        factinv[i] = (factinv[i - 1] * inv[i]);
    }

}

mint nCk(ll n, ll k) {
    if (n < k||k<0) return 0;
    return fact[n] * (factinv[k] * factinv[n - k]);
}


int main(){

    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    
    ll Q;
    cin>>Q;
    ll c=0;
    prenCkModp(3e6);
    vector<ll> P(2e5);
    for(int i=0;i<2e5;i++)P[i]=i;
    P[0]=P[1]=-1;
    for(int i=0;i<2e5;i++)if(P[i]==i){
        for(int j=i;j<2e5;j+=i)P[j]=i;
    }
    for(int i=0;i<Q;i++){
        ll A,B;
        cin>>A>>B;
        while(A>1){
            c++;
            A/=P[A];
        }
        cout<<nCk(c-1,B-1).val()<<endl;
    }
}