#include <fstream>
#include <iostream>
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");

int main()
{
    int n, aux = 0;
    in >> n;
    for (int i = 2; i <= n; i++)
    {
        if (i==2) aux++;
        else if (i == 3) aux ++;
        else if (i == 5) aux++;
        else if (i == 7) aux++;
        else if (i%2 != 0 && i%3!=0 && i%5 !=0 && i%7 !=0)
            aux ++;
    }
    out << aux;
    return 0;
}