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

void fast_io() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
}
#include <atcoder/modint>
using mint = atcoder::modint998244353;
const int M = 5e6;
mint fact[M], inv[M];
void init() {
    fact[0] = 1;
    for (int i = 1; i < M; i++) {
        fact[i] = fact[i - 1] * i;
    }
    inv[M - 1] = fact[M - 1].inv();
    for (int i = M - 2; i >= 0; i--) {
        inv[i] = inv[i + 1] * (i + 1);
    }
}
mint binom(int n, int k) {
    if (k < 0 || n < 0 || n < k) {
        return 0;
    }
    return fact[n] * inv[k] * inv[n - k];
}
int main() {
    fast_io();
    init();
    int q;
    cin >> q;
    int cnt = 0;
    for (; q--;) {
        int a, b;
        cin >> a >> b;
        for (int i = 2; i * i <= a; i++) {
            if (a % i == 0) {
                int c = 0;
                while (a % i == 0) {
                    a /= i;
                    c++;
                }
                cnt += c;
            }
        }
        if (a > 1) {
            cnt++;
        }
        cout << binom(cnt - 1, b - 1).val() << "\n";
    }
}