#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;

int main() {
  int N; cin >> N;
  int A = 0;
  double B = 0.0;
  for(int i = 1; i <= N; i++){
    if(N%i == 0){
      A += i;
      B += 1.0/i;
    }
  }
  int ans = A/B;
  cout << ans << endl;
}