#include<fstream.h>
int main ()
{
int i; 
long n,k=0;
ifstream f("ciur.in");
ofstream g("ciur.out");
f>>n;
if(2<=n) k++;
if(3<=n) k++;
if(5<=n) k++;
if(7<=n) k++;
for(i=2;i<=n;i++)
 if(i%2!=0&&i%3!=0&&i%5!=0&&i%7!=0)
  k++;
g<<k;
f.close();
g.close();
return 0;
}