3numbers

#include<iostream>

#define long long long
#define nln '\n'

using namespace std;

int main()
{
    long n;
    cin >> n;
    long all = 0, co2 = 0, co3 = 0;
    for (long a = 1; a*a*a <= n; ++a)
        for (long b = a; b*b <= n; ++b)
        {
            long c = n/(a*b);
            if (c < b)
                break;
            all += c-b+1;
            if (a == b)
            {
                ++co3;
                co2 += c-b;
            }
            else
                ++co2;
        }
    cout << all*6 - co2*3 - co3*5 << nln;
    return 0;
}