n=gets.to_i
k=i=s=0
while s<n
	k+=1
	s+=(k-2)*~-k/2+1
end
s-=(k-2)*~-k/2+1
while i<k-2&&s<n
	if s+k-2-i>=n
		p ('1'*(i+1)+'0'*(s+k-i-n-1)+'1'*(-s+n)).to_i(2);exit
	else
		s+=k-2-i+=1
	end
end
p 2**k-1