d=int(input())
ans=d
for i in range(1,61):
  def func(x):
    tmp=0
    for _ in range(i):
      tmp+=x
      x//=2
      if x==0:break
    return tmp
  l,r=d//2,d
  while r-l>1:
    x=(l+r)//2
    t=func(x)
    if t==d:
      ans=min(ans,x)
      break
    elif d<t:
      l,r=l,x
    else:
      l,r=x,r
  if func(l)==d:ans=min(ans,l)
  if func(r)==d:ans=min(ans,r)
print(ans)