#include <bits/stdc++.h>
using namespace std;
int main() {
  long long int n{0};
  cin >> n;
  bool flag = false;
  bool flag1 = false;
  long long int i{0}, x{0}, rem{0};
  for (i = 1; i <= 1000000; i++) {
    if (n >= 4 * i && n <= 7 * i) {
      x = 4 * i;
      rem = n - x;
      if ((rem % 3) != 0) {
        x = 0;
        rem = 0;
      } else if (rem % 3 == 0) {
        break;
      }
    }
  }
  if (x == 0 && rem == 0) i = 0;
  if (x == 0) {
    cout << "-1" << endl;
  } else {
    long long int div = rem / 3;
    for (long long int j = 1; j <= i - div; j++) {
      cout << "4";
    }
    for (long long int i = 1; i <= div; i++) {
      cout << "7";
    }
    cout << endl;
  }
  return 0;
}
