#include <iostream>
#include <algorithm>
#include <iomanip>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <numeric>
#include <bitset>
#include <cmath>

static const int MOD = 1000000007;
using ll = long long;
using u32 = uint32_t;
using namespace std;

template<class T> constexpr T INF = ::numeric_limits<T>::max()/32*15+208;

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

int main() {
    ll n;
    cin >> n;
    auto v = divisor(n);
    ll ans = accumulate(v.begin(),v.end(), 0LL);
    cout << ans << "\n";
    return 0;
}