#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;

vector<PLL> prime_factorization(ll x) {
	vector<PLL> res;
	for (ll i = 2; i * i <= x; i++) {
		if (x % i != 0) continue;
		PLL cur = PLL(0, 0);
		cur.first = i;
		while (x % i == 0) {
			cur.second++;
			x /= i;
		}
		res.push_back(cur);
	}
	// xが素数であった場合はxを追加
	if (x != 1) {
		res.push_back(PLL(x, 1));
	}
	return res;
}

void solve(ll x) {
	vector<PLL> factor = prime_factorization(x);
#if 0
	rep(i, factor.size()) {
		cout << factor[i].first << " " << factor[i].second << endl;
	}
#endif

	for (int i = 0; i < factor.size() && factor[i].first != x; i++) {
		ll p = factor[i].first;
		ll size = factor[i].second;
		ll tmp = p;
		rep(j, size) {
			tmp *= p;
		}
		ans *= (tmp - 1) / (p - 1);
	}
	// 最後の素数が自身(x)であった場合
	if (factor.size() > 0 && factor.back().first == x) {
		ans *= (1 + factor.back().first);
	} 
	cout << ans << endl;
}

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