#include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)

using namespace std;
using ll = long long;

const ll INF = 1e18;

void solve() {
    int n;
    cin >> n;
    
    int pc = __builtin_popcount(n);
    if (pc == 1) {
        puts("-1");
        return;
    }
    
    ll ans = INF;
    for (int k = 1; k <= 31; ++k) {
        ll mod = n&((1ll<<k)-1);
        ll x = (1ll<<k) - mod;
        if (x == 0) continue;
        ll y = n+x;
        if (__builtin_popcountll(y) < pc) {
            ans = min(ans, x);
        }
    }
    
    if (ans == INF) ans = -1;
    cout << ans << '\n';
}

int main() {
    int t;
    cin >> t;
    
    while (t--) solve();
    
    return 0;
}