#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  cout.tie(nullptr);
  int t;
  cin >> t;
  while (t--) {
    int n;
    cin >> n;
    if (n == 1) {
      cout << "-1\n";
      continue;
    } else {
      cout << 6;
      for (int i = 1; i <= n - 1; ++i) {
        cout << 7;
      }
      cout << "\n";
    }
  }
  return 0;
}
