#include <bits/stdc++.h>
using namespace std;
int main()
{
int t;
cin >> t;
while (t--)
{
int ans = -1, a, b, c;
scanf("%d", &a);
c = sqrt(a);
if (c * c == a)
{
b = sqrt(c);
if (b * b == c)
ans = b;
}
printf("%d\n", ans);
}
return 0;
}