#include<bits/stdc++.h>
using namespace std;
int main(){
  int n;
  cin>>n;
  int osa_k[n+1];
  iota(osa_k,osa_k+n+1,0);
  for(int i=2;i<=n;i++){
    if(osa_k[i]<i) continue;
    for(int j=2*i;j<=n;j+=i) osa_k[j]=i;
  }
  int ans=0;
  for(int i=2;i<=n;i++){
    vector<int> factors;
    int j=i;
    while(j>1){
      factors.push_back(osa_k[j]);
      j/=osa_k[j];
    }
    sort(factors.begin(),factors.end());
    auto tmp=factors;
    tmp.erase(unique(tmp.begin(),tmp.end()),tmp.end());
    ans+=factors==tmp&&tmp.size()==4;
  }
  cout<<ans<<endl;
}