import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		new Main().solve();
	}

	void solve() {
		Scanner sc = new Scanner(System.in);
		long N = sc.nextLong();
		long ans = N;
		long cur = 0;
		while (N > 0) {
			ans = Math.max(cur + 2 * N, ans);
			cur += N;
			N /= 2;
		}
		System.out.println(ans - cur);
	}
}