#include<bits/stdc++.h>
using namespace std;
int yinzi(int n)
{
	int r=0;
	for(int i=1;i<=n/2+1;i++)
	{
		if(n%i==0)
		{
			r+=i;
		}
	}
	return r;
}
int main()
{
	int n,cnt=0;
	cin>>n;
	for(int i=2;i<=n;i++)
	{
		if(yinzi(i)==i)
		{
			cnt++; 
		}
	}
	cout<<cnt;
	return 0;
}
/**************************************************************
	Problem: 1150
	User: wangyuxin
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/