3726

def rsum(a):
    a = str(a)
    s = 0
    for i in a:
        s += int(i)

    return s

for N in range(10000000, 100000000):
    n = rsum(N)
    n = bin(n)[2::]

    if n.count('1') % 2 == 0:
        n = '1' + n + '00'
    else:
        n = '10' + n + '1'

    r = int(n, 2)
    if r == 21:
        print(N)