#include <bits/stdc++.h>
using namespace std;
const int inf = (int)1e9;
const long long int INF = (long long int)1e18;
const int N = 100005;
const long long int MOD = 1000000007;
const double EPS = 1e-7;
const double PI = acos(-1.0);
const int dx[] = {+1, -1, +0, +0};
const int dy[] = {+0, +0, +1, -1};
const int hx[] = {-2, -2, -1, -1, +1, +1, +2, +2};
const int hy[] = {+1, -1, +2, -2, +2, -2, +1, -1};
const int fx[] = {-1, +0, +1, +0, +1, +1, -1, -1, +0};
const int fy[] = {+0, -1, +0, +1, +1, -1, +1, -1, +0};
template <typename T>
inline T GCD(T a, T b) {
  a = abs(a), b = abs(b);
  return !b ? a : GCD(b, a % b);
}
template <typename T>
inline T LCM(T x, T y) {
  T g = GCD(x, y);
  return x * y / g;
}
template <typename T>
inline T BigMod(T b, T p, T mod) {
  T res = 1 % mod, x = b % mod;
  while (p) {
    if (p & 1) res = (res * x) % mod;
    x = (x * x) % mod;
    p >>= 1;
  }
  return res;
}
template <typename T>
inline T ModInv(T val, T mod) {
  return BigMod(val, mod - 2, mod);
}
template <typename T>
inline T bigmod(T b, T p, T mod) {
  if (p == 0) return 1;
  T x = bigmod(b, p / 2, mod);
  x = (x * x) % mod;
  if (p % 2 == 1) x = (b * x) % mod;
  return x;
}
template <typename T>
inline T NumDigit(T num, T base) {
  return ((T)(log10((num)) / log10((base)))) + 1;
}
template <typename T>
inline T Power(T b, T p) {
  T res = 1, x = b;
  while (p) {
    if (p & 1) res = (res * x);
    x = (x * x);
    p >>= 1;
  }
  return res;
}
template <typename T>
inline T IsPrime(T x) {
  if (x < 2) return false;
  for (T i = 2; i * i <= x; i++) {
    if (x % i == 0) return false;
  }
  return true;
}
template <typename T>
inline T SumDigit(T x) {
  T ret = 0;
  while (x) {
    ret += x % 10, x /= 10;
  }
  return ret;
}
int main(int argc, char const *argv[]) {
  int n;
  scanf("%d", &n);
  for (int i = 0; i * 4 <= n; i++) {
    for (int j = 0; i * 4 + j * 7 <= n; j++) {
      if (4 * i + j * 7 == n) {
        for (int m = 1; m <= i; m++) printf("4");
        for (int m = 1; m <= j; m++) printf("7");
        return 0;
      }
    }
  }
  printf("-1\n");
  return 0;
}
