#include<cstdio>
int N;
void ciur()
{ int x=0,i;
	switch(N)
	{
	case 2: x=1;
	case 3: x=2;
	case 4: x=2;
	case 5: x=3;
	case 6: x=3;
	}
	if(N>=7)
		x=4;
	for(i=2;i<=N;i++)
		if((i%2!=0)&&(i%3!=0)&&(i%5!=0)&&(i%7!=0))
			x++;
	printf("%d",x);
}
int main()
{
	freopen("ciur.in","r",stdin);
	freopen("ciur.out","w",stdout);
	scanf("%d",&N);
	ciur();
	return 0;
}