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

using ll = long long;

bool chmin(auto &a, auto b) { return a > b ? a = b, true : false; }
bool chmax(auto &a, auto b) { return a < b ? a = b, true : false; }

void solve(map<string, int> &mp) {
    string N; cin >> N;
    int ans = 2'000'000'000;
    sort(N.begin(), N.end(), greater());
    while(N.size() > 0) {
        if(N.back() == '0') N.pop_back();
        else break;
    }
    while(N.size() < 10) {
        if(mp.count(N)) chmin(ans, mp[N]);
        N += '0';
    }
    if(ans == 2'000'000'000) cout << -1 << endl;
    else cout << ans << endl;
    return;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    map<string, int> mp;
    for(int i=1; i*i<=1'000'000'000; ++i) {
        int y = i*i;
        string x = to_string(y);
        sort(x.begin(), x.end(), greater());
        if(!mp.count(x)) mp[x] = y;
    }
    int T; cin >> T;
    for(int i=0; i<T; ++i) solve(mp);
}