#include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
#define UNIQUE(v) v.erase( unique(v.begin(), v.end()), v.end() );
using namespace std;
using ll = long long;
void chmin(ll &x, ll y) { x = min(x, y); }
void chmax(ll &x, ll y) { x = max(x, y); }
const ll INF = 1e9;
const ll MOD = 1e9 + 7;

// 約数列挙
vector<long long> calc_divisor(long long n) {
    vector<long long> res;
    for (long long i = 1LL; i*i <= n; ++i) {
        if (n % i == 0) {
            res.push_back(i);
            long long j = n / i;
            if (j != i) res.push_back(j);
        }
    }
    sort(res.begin(), res.end());
    //sort(res.rbegin(), res.rend());
    return res;
}


int main(){
    ll n;
    cin >> n;
    auto d = calc_divisor(n);
    ll ans = 0;
    rep(i, d.size()) ans += d[i];
    cout << ans << endl;
}