#include<stdio.h>
#include<iostream.h>
FILE *f=fopen("ciur.in","r");
FILE *g=fopen("ciur.out","w");
long n,k,i;
int main(){
	fscanf(f,"%ld",&n);
	k=0;
	for(i=2;i<=n;i++)
		if((i==2)||(i==3)||(i==5)||(i==7)||(i%2!=0&&i%3!=0&&i%5!=0&&i%7!=0))
			k=k+1;
	fprintf(g,"%d",k);
	fclose(f);
	fclose(g);
	return 0;}