#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
#define int long long
#define debug(x) cout << #x << " = " << x << '\n'

const int N = 1e6 + 10;
const int inf = 0x3f3f3f3f3f3f3f3f;
const int mod = 998244353;

int MAX;
vector<int> f[N];

void solve() {
    int n;
    cin >> n;

    if (n % 3 == 0) {
        int x = n / 3;
        cout << x * x * x << '\n';
    } else if (n % 4 == 0) {
        int x = n / 2, y = n / 4;
        cout << x * y * y << '\n';
    } else {
        cout << "-1\n";
    }
}

signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);
    int t = 1;
    cin >> t;
    while(t--) solve();
}