#include <iostream>
#include <cmath>
using namespace std;

int main() {
	long long n;
	cin >> n;
	if (n <= 3) cout << n;
	else {
		long long pow, a = 2, b = 3;
		pow = log (n) / log (2);
		a = a << (pow - 1);
		b = b << (pow - 1);
		if (a <= n && b <= n) cout << max(a, b);
		else if(a > n) cout << b ;
			else cout << a;
	}
	return 0;
}