using static System.Math;
using System;

public class Hello
{
    static void Main()
    {
        var n = long.Parse(Console.ReadLine().Trim());
        getAns(n);
    }
    static void getAns (long n)
    {
        var ans = long.MaxValue;
        for (int k = 0; k < 65; k++)
        {
            var w = BS(n, k);
            if (w != -1) ans = Min(ans, w);
        }
        Console.WriteLine(ans);
    }
    static long BS (long targ, int k)
    {
        var ng = 1L;
        var ok = targ;
        while (ok - ng > 1)
        {
            var mid = ng + (ok - ng) / 2;
            var w = calc(mid, k);
            if (w == targ) return mid;
            else if (w > targ) ok = mid;
            else ng = mid;
        }
        return -1;
    }
    static long calc (long n , int k)
    {
        var res = n;
        var p = 1;
        while (p < k && n >0)
        {
            n /= 2;
            res += n;
            p++;
        }
        return res;
    }
}