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

using ll = long long;
#define rep(i, n) for(int i = 0; i < n; i++)

int main() {
	ll N;
	cin >> N;
	vector<int> p{2, 3, 5, 7, 11, 13, 17, 19, 23, 29,
					31, 37, 41, 43, 47, 53, 59, 61, 67, 71,
					73, 79, 83, 89, 97,};
	int sz = p.size();
	int ans = 0;
	rep(i, sz) {
		if(N / p[i] == 0) break;
		ans++;
		N /= p[i];
	}
	cout << ans << endl;
}