#include <bits/stdc++.h>
#define For(i,a,b) for(int i=(a);i<=(b);++i)
#define Rep(i,a,b) for(int i=(a);i>=(b);--i)
#define int long long
using namespace std;

typedef vector<int>vi;
#define pb push_back

#define maxn 4000005
int pri[maxn],tot;
bool vis[maxn];

int sum[maxn];
void sieve(int n){
    vis[1]=1;
    For(i,2,n){
        if(!vis[i]){
            pri[++tot]=i;
        }
        For(j,1,tot){
            int x=i*pri[j];
            if(x>n)break;
            vis[x]=1;
            if(i%pri[j]==0)break;
        }
    }
    For(i,1,n) sum[i]=sum[i-1]+(!vis[i]);
}

int n,B;
int res;
void dfs(int u,int xs,int id){
    if(u>n) return;
    ++res;
  //  cout<<"add "<<u<<"\n";
    for(int i=id; i<=tot; ++i){
        if(u*pri[i]>n) break;
        if(pri[i]>xs+1) break;
        if(u*pri[i]*pri[i]>n){
            int r=min(xs+1,n/u);
            res+=sum[r]-sum[pri[i]-1];
            return;
        }
        int p=pri[i];
        int v=u,sv=1,pw=1;
        for(int j=1; ;++j){
            pw*=p;
            sv+=pw;
            v*=p;
            if(v>n)break;
            dfs(v,xs*sv,i+1);
        }
    }
}


signed main()
{
    cin>>n;
    B=sqrt(n)+1;
    sieve(3000005);
    dfs(1,1,1);
    cout<<res;
	return 0;
}

/*
1000000000000
50
1 2 4 6 8 12 16 18 20 24 28 30 32 36 40 42 48
*/