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

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

int main() {
    long long n; cin >> n;
    vector<long long> D = divList(n);
    long long sum = 0;
    for(auto d : D) sum += d;
    cout << sum << '\n';
    return 0;
}