#include <bits/stdc++.h>

using namespace std;

#define int long long

const int N = 1e6 + 5, mod = 998244353;

int x = 1, inv[N], g[N], f[N], cnt = 0;

int mypow(int a, int b) {
  int ans = 1;
  while (b) {
    if (b & 1) {
      ans = ans * a % mod;
    }
    a = a * a % mod;
    b >>= 1;
  }
  return ans;
}

int C(int n, int m) {
  return f[n] * g[m] % mod * g[n - m] % mod;
}

void Solve() {
  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++;
  }
  if (cnt < b) {
    cout << "0\n";
  }
  else cout << C(cnt - 1, b - 1) << "\n";
}

signed main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  inv[1] = f[0] = g[0] = 1;
  for (int i = 1; i <= 1000000; i++) {
    f[i] = f[i - 1] * i % mod;
    if (i > 1) inv[i] = inv[mod % i] * (mod - mod / i) % mod;
    g[i] = g[i - 1] * inv[i] % mod;
  }
  int n;
  cin >> n;
  for (int i = 1; i <= n; i++) {
    Solve();
  }
  return 0;
}

/*
.|.|.|.|.
4 * 3 * 2 * 1
*/