#include <bits/stdc++.h>
#define ll long long
using namespace std;

void input(){
	#define taskname ""
	if(fopen(taskname ".inp", "r")){
		freopen(taskname ".inp", "r", stdin);
		freopen(taskname ".out","w",stdout);
	}
}
const int N = 1e6;
ll tonguoc(ll n){
	ll sum =0;
	for(ll i =1; i*i <=n;++i){
		if( n % i == 0){
			sum += i;
			if(i != n/i) sum += n/i;
		}
	}
	return sum;
}
ll n;
int main(){
	input();
	cin.tie(0)->sync_with_stdio(0);
	cin >> n;
	cout << tonguoc(n) << endl;
	return 0;
}