d = int(input())


def  cal(a):
    cnt = 0
    for i in range(k):
        cnt += a
        a//=2
    return cnt

ans = d
for k in range(65):
    ng = 0
    ok = d
    while ok - ng > 1:
        mid = (ok + ng)//2
        t=cal(mid)
        if  t >= d:
            ok = mid
        else:
            ng = mid
    if cal(ok) == d:
    	ans = min(ans,mid)


print(ans)