#include <bits/stdc++.h>
#define int long long
using namespace std;
long getDataDependenceSum(long n) {
    int sum = 0, x = 1;
    map<int, int> seen;
    while(x * x <= n) {
        if(!seen.count(x)) {
            sum += x;
            seen[x] = 1;
        }
        if(!seen.count(n / x)) {
            sum += n / x;
            seen[n / x] = 1;
        }
        x++;
    }
    return sum;
}
signed main()
{
    cout << getDataDependenceSum(13) << endl;
    return 0;
}