#include"bits/stdc++.h"

//#include<bits/stdc++.h>
using namespace std;
#define print(x) cout<<x<<endl;
#define rep(i,a,b) for(int i=a;i<b;i++)
#define REP(i,a) for(int i=0;i<a;i++)
typedef long long ll;
const ll mod = 10000000000;

int main() {
	ll n;
	cin >> n;
	vector<int> v;
	ll ans = 0;
	rep(i,1, i*i <= n) {
		if (n%i == 0) {
			ans += i;
		}
	}
	if (n % 2 == 1)ans += n;
	print(ans);
	return 0;
}