#include <bits/stdc++.h>
using namespace std;
void work()
{
    long long n, m;
    cin >> n >> m;
    if (m % n != 0)
    {
        cout << "-1\n";
        return;
    }
    int ans = 0;
    while (n != m)
    {
        long long k = m / n;
        long long d = __gcd(n, k);
        if (d == 1)
        {
            cout << "-1\n";
            return;
        }
        n = n * d;
        ans++;
    }
    cout << ans << "\n";
}
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int T;
    cin >> T;
    while (T--)
        work();
    return 0;
}