#include <stdio.h>

long long gcd (long long a, long long b) {
  if (b <= 0LL) {
    return a;
  }
  
  return gcd(b, a%b);
}

long long power_mod (long long a, long long b, long long mod_num) {
  long long ans = 1LL;
  
  if (b > 0LL) {
    ans = power_mod(a, b/2LL, mod_num);
    ans = (ans * ans) % mod_num;
    if (b%2LL == 1LL) {
      ans = (ans * a) % mod_num;
    }
  }
  
  return ans;
}

int main () {
  int t = 0;
  long long h = 0LL;
  long long w = 0LL;
  
  int res = 0;
  
  long long mod_num = 998244353LL;
  
  long long div[1000] = {};
  
  res = scanf("%d", &t);
  while (t > 0) {
    long long ans = 0LL;
    long long d = 0LL;
    int div_cnt = 0;
    res = scanf("%lld", &h);
    res = scanf("%lld", &w);
    d = gcd(h, w);
    for (int i = 1; i*i <= ((int)d); i++) {
      if (((int)d)%i == 0) {
        div[div_cnt] = (long long)i;
        div_cnt++;
        if (((int)d)/i != i) {
          div[div_cnt] = d/((long long)i);
          div_cnt++;
        }
      }
    }
    for (int i = 0; i < div_cnt; i++) {
      if (div[i] == 4LL) {
        ans += 16LL;
        ans %= mod_num;
      } else if (div[i] >= 10LL && (div[i]-10LL)%6LL == 0LL) {
        long long tmp = power_mod((div[i]-4LL)/3LL, d/div[i]-1LL, mod_num);
        tmp *= (div[i]*div[i])%mod_num;
        tmp %= mod_num;
        ans += tmp;
        ans %= mod_num;
      }
    }
    ans += h*w;
    ans %= mod_num;
    if (d > 3LL) {
      ans += 2LL*d;
      ans %= mod_num;
    }
    if (d > 3LL && d%3LL == 0LL) {
      ans += 6LL*d;
      ans %= mod_num;
    }
    printf("%lld\n", ans);
    t--;
  }
  
  return 0;
}