#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int mod = 1e9 + 7;
const int inf = (1 << 30) - 1;
const ll infll = (1LL << 61) - 1;
#define fast() cin.tie(0), ios::sync_with_stdio(false)

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

ll N, ans;

int main()
{
    cin >> N;
    auto d = divisor(N);
    for (auto &a : d)
    {
        ans += a;
    }
    cout << ans << endl;
}