#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
template<class T> inline bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T> inline bool chmin(T&a,T b){if(a>b){a=b;return 1;}return 0;}
using ll = long long;

ll n,ans;

vector<ll> divisor(ll n){
    vector<ll> ret;
    for(ll i=1;i*i<=n;i++){
        if(n%i==0){
            ret.push_back(i);
            if(i*i!=n) ret.push_back(n/i);
        }
    }
    sort(ret.begin(), ret.end()); 
    return ret;
}

int main () {
    cin.tie(0); ios::sync_with_stdio(false); 

    cin >> n;
    for(auto a : divisor(n)) ans+=a;
    cout << ans << endl;
}