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

ll n, ok=0;
int main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin >> n;
    for(int i=1; i*i<=n; ++i)
    {
        if(n%i==0)
        {
            ok+=i;
            if(n/i!=i) {ok+=n/i;}
        }
    }
    cout << ok;
    return 0;
}