#include <iostream>

using namespace std;

int main() {
    long long n, cnt = 0;
    cin >> n;

    for (long long a = 1; a * a * a <= n; a++) {
        for (long long b = a; a * b * b <= n; b++) {
            long long max_c = n / (a * b);
            if (max_c >= b) cnt += max_c - b + 1;
        }
    }

    cout << cnt << endl;

    return 0;
}