#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <numeric>
#include <bitset>
#include <complex>
#define rep(x, to) for (int x = 0; x < (to); x++)
#define REP(x, a, to) for (int x = (a); x < (to); x++)
#define foreach(itr, x) for (typeof((x).begin()) itr = (x).begin(); itr != (x).end(); itr++)
#define EPS (1e-14)

using namespace std;

typedef long long ll;
typedef pair<int, int> PII;
typedef pair<ll, ll> PLL;
typedef complex<double> Complex;
typedef vector< vector<int> > Mat;

ll N;
ll ans = 1;

void solve(ll x) {

	for (ll i = 2; i * i <= x; i++) {
		if (x % i != 0) continue;
		ll power = 1;
		while (x % i == 0) {
			power *= i;
			x /= i;
		}
		power *= i;
		ans *= (power - 1) / (i - 1);
	}
	// Nが素数の場合
	if (x != 1) {
		ans *= 1 + x;
	}
	cout << ans << endl;
}

int main() {
	cin >> N;
	solve(N % 2 == 0 ? N / 2 : N);
	return 0;
}