/* -*- coding: utf-8 -*-
 *
 * 278.cc: No.278 連続する整数の和(2) - yukicoder
 */

#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<iostream>
#include<string>
#include<vector>
#include<map>
#include<set>
#include<stack>
#include<list>
#include<queue>
#include<deque>
#include<algorithm>
#include<numeric>
#include<utility>
#include<complex>
#include<functional>
 
using namespace std;

/* constant */

/* typedef */

typedef long long ll;

/* global variables */

/* subroutines */

ll gcd(ll m, ll n) {  // m >= n > 0
  while (n > 0) {
    ll r = m % n;
    m = n;
    n = r;
  }
  return m;
}

/* main */

int main() {
  ll n;
  cin >> n;

  if (n == 1) {
    puts("1");
    return 0;
  }

  ll m = n * gcd(2, n - 1) / 2;

  ll sum = 0;
  for (ll p = 1; p * p <= m; p++)
    if (m % p == 0) {
      ll q = m / p;
      if (p == q) sum += p;
      else sum += p + q;
    }

  printf("%lld\n", sum);
  return 0;
}