D=int(input())
L=D//2
R=D
while L!=R:
    now=(L+R)//2
    count=0
    while now>0:
        count+=now
        now//=2
    if count>=D:
        R=(L+R)//2
    else:
        L=(L+R)//2+1
ok=0
for _ in range(10**8):
    count=0
    now=L
    while now>0:
        count+=now
        now//=2
    if count==D:
        ok=1
        break
    L+=1

print(L if ok else D)