#include <bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using ll =  long long ;
using P = pair<int,int> ;
const int INF = 1e9;
const int MOD = 1000000007;

vector<ll> diviser_all(ll x){
        vector<ll> res;
        for(ll i = 1;i*i <=x;i++){
                if(x%i == 0){
                        res.push_back(i);
                        if(i*i==x);
                        else res.push_back(x/i);
                }
        }
        return res;
}

int main(){
    ll n;
    cin >> n;
    vector<ll> res = diviser_all(n);
    ll ans = 0;
    for(ll p:res) ans += p;
    cout << ans << endl;
    return 0;
}