#include <stdio.h>

using namespace std;

int main()
{
    freopen("ciur.in","r",stdin);
    freopen("ciur.out","w",stdout);

    int n;
    int i, cate=1;
    scanf("%d", &n);

    for( i=3; i <= n ; i++)
        if( (i%2!=0 && i%3!=0 && i%5!=0 && i%7!=0) || i==2 ||i==3 ||i==5||i==7)
           // cout << i << " ",
            cate++;

    printf("%d", cate);

    return 0;
}