#include <bits/stdc++.h>

using namespace std;

#define REP(i,n) for(int i=0; i<(int)(n); i++)
#define FOR(i,b,e) for (int i=(int)(b); i<(int)(e); i++)
#define ALL(x) (x).begin(), (x).end()

const double PI = acos(-1);

vector<long long> divisor(long long n) {
  vector<long long> ret;
  for (long long i = 1; i * i <= n; i++) {
    if (n % i == 0) {
      ret.push_back(i);
      if (i != n / i)
        ret.push_back(n / i);
    }
  }
  return ret;
}

int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  
  long long n;
  cin >> n;

  long long sum = 0;
  for (long long d : divisor(n))
    sum += d;

  cout << sum << endl;
  
  return 0;
}