#include <bits/stdc++.h>
using namespace std;

const int INF = 2e9;
const int primes[] = {2, 3, 5};

int p2[32];

inline int lgput(int x, int p, int MOD) {
    int ans = 1, aux = x;

    for (int i = 1; i <= p ; i = i << 1) {
        if (i & p) ans = (1LL * ans * aux) % MOD;
        aux = (1LL * aux * aux) % MOD;
    }

    return ans;
}

inline bool fermatCheck(int n, int x, int d, int base) {
    int p = lgput(base, x, n);
    if (p == 1 || p == n - 1) return true ;

    for (int i = 0; i <= d ; ++i) {
        p = 1LL * p * p % n;
        if(p == n - 1) return true ;
    }

    return false;
}

bool checkPrime(int n) {
    if (n < 2) return false;

    int x = n - 1, d = 0;
    while (x % 2 == 0) {
        x = x >> 1;
        ++d;
    }

    for (auto base : primes)
        if (!fermatCheck(n, x, d, base)) return false;

    return true;
}

int main() {

//    for (int i = 1; i <= 100 ; ++i) {
//        cerr << i << " ";
//        if(checkPrime(i)) cerr << "is prime";
//        else cerr << "isn't prime";
//
//        cerr << endl;
//    }

    freopen("ciur.in", "r", stdin);
    freopen("ciur.out", "w", stdout);

    p2[0] = 1;
    for (int i = 1; i <= 30 ; ++i) p2[i] = p2[i - 1] * 2;

    int n;
    scanf("%d", &n);

    int ans = 4;
    for (int i = 11; i <= n ; i += 2) {
        if (i % 3 == 0 || i % 5 == 0) continue ;
        if (checkPrime(i)) ++ans;
    }

    printf("%d", ans);

    return 0;
}