#include <bits/stdc++.h>
 
using namespace std;
 
#define LL long long
 
int n;
 
int main() {
    cin >> n;
    int best = 1000000000;
    for(int i = 1; i <= n; i++) {
        if(n % i == 0) {
            best = min(best, i + n / i);
        }
    }
    cout << best * 2;
}