/*** author: yuji9511 ***/
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<ll, ll> lpair;
const ll MOD = 1e9 + 7;
const ll INF = 1e18;
#define rep(i,m,n) for(ll i = (m); i < (n); i++)
#define rrep(i,m,n) for(ll i = (m); i >= (n); i--)
#define print(x) cout << (x) << endl;
#define print2(x,y) cout << (x) << " " << (y) << endl;
#define printa(x,n) for(ll i = 0; i < n; i++){ cout << (x[i]) << " \n"[i==n-1];};
struct Integer{
public:

    ll gcd(ll a,ll b){return b ? gcd(b, a % b) : a;} //最大公約数

    ll lcm(ll a,ll b){return a / gcd(a, b) * b;} //最小公倍数

    bool isPrime(ll x){
        if(x < 2) return false;
        if(x == 2) return true;
        if(x % 2 == 0) return false;
        for(ll i = 3;i <= sqrt(x) + 1;i += 2) if(x % i == 0) return false;
        return true;
    }

    vector<ll> divisor(ll M){ //約数の全列挙
        vector<ll> dd;
        for(ll i = 1; i * i <= M; i++){
            if(M % i == 0){
                dd.push_back(i);
                if(i * i != M){
                    dd.push_back(M / i);
                }
            }
        }
        sort(dd.begin(), dd.end());
        return dd;
    }

    vector<ll> factor(ll M){ //素因数分解
        vector<ll> dd;
        if(M == 1){
            dd.push_back(1);
            return dd;
        }
        for(ll i = 2; i*i <= M; i++){
            while(M % i == 0){
                dd.push_back(i);
                M /= i;
            }
        }
        if(M != 1) dd.push_back(M);
        sort(dd.begin(), dd.end());
        return dd;
    }
};

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	ll N;
	cin >> N;
	Integer it;
	vector<ll> dd = it.divisor(N);
	ll ans = 0;
	for(auto &e: dd) ans += e;
	print(ans);


	
}