#include<bits/stdc++.h>
using namespace std;
#define ll long long
ll a;
ll s = 1;
int main() {
    cin >> a;
    ll n = a;
    s += a;
    for(int i = 2; i * i <= a; i++) {
        ll c = 0;
        while(a % i == 0) {
            a /= i;
            c++;
        }
        s += (c * i);
    }
    if(a > 1 && a != n) {
        s += a;
    }
    cout << s;
    return 0;
}