#include <bits/stdc++.h>
#define int long long
using namespace std;
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t;cin>>t;
    vector<int>sq;
    for(int i=1;i<=1e5;i++)sq.push_back(i*i);
    map<vector<int>,int>num;
    for(int i=0;i<sq.size();i++){
        string st=to_string(sq[i]);
        vector<int>mem;
        for(int i=0;i<st.size();i++)mem.push_back(st[i]-'0');
        sort(mem.begin(),mem.end());
        reverse(mem.begin(),mem.end());
        if(num.find(mem)==num.end())num[mem]=sq[i];
        else if(sq[i]<num[mem])num[mem]=sq[i];
    }
    // for(auto[lst,nu]:num){
    //     cout<<"lst | ";
    //     for(int i:lst)cout<<i<<" ";cout<<endl;
    //     cout<<"num -> "<<nu<<endl;
    // }
    while(t--){
        string s;cin>>s;
        int ans=1e18;
        vector<int>ch;
        for(int i=0;i<s.size();i++)ch.push_back(s[i]-'0');
        sort(ch.begin(),ch.end());
        reverse(ch.begin(),ch.end());
        if(num.find(ch)!=num.end())ans=min(ans,num[ch]);
        while(ch.back()==0){
            ch.pop_back();
            if(num.find(ch)!=num.end())ans=min(ans,num[ch]);
        }
        if(ans==1e18)cout<<-1<<"\n";
        else cout<<ans<<endl;
    }
}