#include <bits/stdc++.h>
using namespace std;
int main() {
  int k;
  cin >> k;
  if (k < 25) {
    cout << -1 << endl;
  } else {
    int r = 0, c = 0;
    for (int i = 5; i <= sqrt(k); i++) {
      if (k % i == 0) {
        r = i;
        c = k / i;
        break;
      }
    }
    if (r == 0 or c == 0) {
      cout << -1 << endl;
    } else {
      char ch[] = {'a', 'e', 'i', 'o', 'u'};
      string fr = "";
      for (int j = 0; j < r; j++) {
        for (int i = 0; i < c; i++) {
          fr += ch[(j + i) % 5];
        }
      }
      cout << fr << endl;
    }
  }
}
