import java.util.*;

public class Main {
	public static void main (String[] args) {
		Scanner sc = new Scanner(System.in);
		long d = sc.nextLong();
		long left = 0;
		long right = d;
		while (right - left > 1) {
		    long m = (left + right) / 2;
		    long x = m;
		    long sum = 0;
		    while (x > 0) {
		        sum += x;
		        x /= 2;
		    }
		    if (sum >= d) {
		        right = m;
		    } else {
		        left = m;
		    }
		}
		long sum = 0;
		long x = right;
		while (x > 0 && sum < d) {
		    sum += x;
		    x /= 2;
		}
		if (sum == d) {
		    System.out.println(right);
		} else {
		    System.out.println(d);
		}
   }
}