#include <bits/stdc++.h>
using namespace std;

/*
ショトカ登録
cin cout endl return
int double string char
pair make_pair first second tuple make_tuple
sort erase swap
stoi to_string
auto bool true false
vector queue priority_queue front pop_frpnt
size substr push_back pop_back push pop top
if for while break continue next_permutation
__builtin_popcount 
*/

//無限
int inf = 1020304050;
int64_t INF = 1020304050607080900;

//モッド
int64_t mod = 998244353;

//all マクロ
#define all(v) v.begin(), v.end()


int main () {
    //少数以下
    cout << fixed << setprecision(15);

    map<vector<int>, int> M;
    for (int i = 1; i < 40000; i++) {
        vector<int> l(9, 0);
        int j = i * i;
        string s = to_string(j);
        for (auto x : s) {
            int k = x - '0';
            if (k == 0) continue;
            l[k - 1]++;
        }
        if (M.count(l) == 0) {
            M[l] = j;
        }
    }

    int TT; cin >> TT;
    for (int tt = 0; tt < TT; tt++) {
        int N; cin >> N;
        string S = to_string(N);
        vector<int> L(9, 0);
        for (auto x : S) {
            int k = x - '0';
            if (k == 0) continue;
            L[k - 1]++;
        }
        if (M.count(L) == 0) cout << -1 << endl;
        else {
            cout << M.at(L) << endl;
        }
    }
}