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

using ll = long long;
#define FOR(i, m, n) for (int i = (m); i < (n); i++)
#define REP(i, n) FOR(i, 0, n)
#define REP1(i, n) FOR(i, 1, (n) + 1)
#define ALL(c) (c).begin(), (c).end()
template<class T> inline bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return false;}
template<class T> inline bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return false;}
const int MOD = 1000000007;
const int INF = 1000000001;

vector<ll> divisors(ll n) {
    vector<ll> v;
    for (ll i = 1; i * i <= n; i++) {
        if (n % i == 0) {
            v.push_back(i);
            if (i * i != n) {
                v.push_back(n / i);
            }
        }
    }
    return v;
}

int main() {
    ll n;
    cin >> n;
    vector<ll> d = divisors(n);
    ll t = 0;
    for (ll x : d) {
        t += x;
    }
    cout << t << endl;
}