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

using ll=long long;
map<string,ll> mp;

void solve(){
  string n;
  cin>>n;
  sort(n.begin(),n.end());
  if (mp[n]==0) cout<<-1<<endl;
  else cout<<mp[n]<<endl;
}

int main(){
  for (ll i=0;i<1e6;i++){
    string s=to_string(i*i);
    sort(s.begin(),s.end());
    if (!mp.count(s)) mp[s]=i*i;
    while (s.size()<=12){
      s="0"+s;
      if (mp.count(s)) continue;
      mp[s]=i*i;
    }
  }
  int t;
  cin>>t;
  while (t--) solve();
}