#include<bits/stdc++.h>
using namespace std;
int t,x,z;
int main()
{
    cin>>t;
    while(t--)
    {
        cin>>x>>z;
        if(z%x!=0)
        {
            cout<<-1<<endl;
            continue;
        }
        int num1=z/x,num2=__gcd(num1,x*x),num3=(int)sqrt(num2);
        if(num3*num3!=num2)cout<<-1<<endl;
        else cout<<num1/num3<<endl;
    }
    return 0;
}