#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000005
#define Inf64 1000000000000000001LL


int main(){
	map<vector<int>,long long> mp;
	for(long long i=1;i*i<=1000000000;i++){
		long long t = i*i;
		vector<int> v(10);
		while(t>0){
			v[t%10]++;
			t/=10;
		}
		if(mp[v]==0)mp[v] = i*i;
	}
	int _t;
	cin>>_t;
	rep(_,_t){
		long long ans = Inf64;
		long long n ;
		cin>>n;
		vector<int> v(10);
		while(n>0){
			v[n%10]++;
			n /= 10;
		}
		while(v[0]>=0){
			if(mp.count(v))ans = min(ans,mp[v]);
			v[0]--;
		}
		if(ans==Inf64)ans = -1;
		cout<<ans<<endl;
	}
	return 0;
}