#include<bits/stdc++.h>

using namespace std;

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

int f[N], g[N], inv[N], p[N], a, b, cnt, vis[N], q;
vector<int>e;

int C(int n, int m){
  if(m > n)return 0;
  return 1ll * f[n] * g[m] % mod * g[n - m] % mod;
}

int main(){
  f[0] = g[0] = inv[1] = 1;
  for(int i = 1; i <= 1000000; i++){
    f[i] = 1ll * f[i - 1] * i % mod;
    if(i > 1){
      inv[i] = 1ll * inv[mod % i] * (mod - mod / i) % mod;
    }
    g[i] = 1ll * g[i - 1] * inv[i] % mod;
  }
  for(int i = 2; i <= 100000; ++i){
    if(!vis[i]){
      e.push_back(i);
      p[i] = i;
    }
    for(auto v : e){
      if(1ll * v * i > 100000)break;
      vis[v * i] = 1;
      p[v * i] = v;
      if(i % v == 0)break;
    }
  }
  cin >> q;
  while(q--){
    cin >> a >> b;
    for(; a > 1; a /= p[a], cnt++){
    }
    cout << C(cnt - 1, b - 1) << '\n';
  }
  return 0;
}