#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define ALL(v) v.begin(),v.end()
#define dbg(x) cerr << #x << ": " << (x) << endl;
ll mod = 998244353;
struct Comb {
    int n;
    ll mod;
    vector<ll> fac, finv, inv;
    Comb(int n, ll mod) : n(n), mod(mod), fac(n+1), finv(n+1), inv(n+1) {
        fac[0] = fac[1] = inv[1] = finv[0] = finv[1] = 1;
        for (int i = 2; i <= n; ++i) {
            fac[i] = (fac[i-1] * i) % mod;
            inv[i] = mod - inv[mod%i] * (mod/i) % mod;
            finv[i] = finv[i-1] * inv[i] % mod;
        }
    }
    ll c(int n, int k) {
        if (n < k || k < 0) return 0;
        return fac[n] * finv[k] % mod * finv[n-k] % mod;
    }
} cb(17e5, mod);
int q;
int main() {
    cin >> q;
    int cnt = 0;
    while (q--) {
        int a,b;
        cin >> a >> b;
        for (int i = 2; i*i <= a; ++i) {
            while (a % i == 0) {
                ++cnt;
                a /= i;
            }
        }
        if (a > 1) ++cnt;
        cout << cb.c(cnt-1, b-1) << '\n';
    }
}