#include<bits/stdc++.h>

using namespace std;

long int x,a[2000000],b[2000000],k;
bool f[2000000];

int main(){
	ifstream cin("ciur.in");
	ofstream cout("ciur.out");
	cin>>x;
	for(int i=2;i<=x;i++){
		if(i%2==0) f[i]=1;
		if(i%3==0) f[i]=1;
		if(i%5==0) f[i]=1;
	}
	for(int i=2;i<=x;i++){
		if(f[i]==0) k++;
	}
	if(x<=2) cout<<1;
	else if(x==3) cout<<2;
	else if(x<=5&&x>3) cout<<3;
	else cout<<k+3;
	return 0;
}