#include<bits/stdc++.h>
using namespace std;
bool wm(int n){
	bool r=true;
	int s=1;
	for(int i=2;i<=sqrt(n);i++){
		if(n%i==0) s=s+i+n/i;
	}
	if(s==n)r=true;
	else r=false;
	return r;
}
int main(){
	int n,o=0;
	cin>>n;
	for(int i=2;i<=n;i++){
		if(wm(i)) o++;
		
		
		
		
		
	}
	
	cout<<o;




	return 0;
}

/**************************************************************
	Problem: 1150
	User: wuzihang
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/