18663929856 has 576 divisors, whose sum is σ = 64858116960. Its totient is φ = 5096079360.

The previous prime is 18663929819. The next prime is 18663929887. The reversal of 18663929856 is 65892936681.

It is a tau number, because it is divible by the number of its divisors (576).

It is a junction number, because it is equal to n+sod(n) for n = 18663929793 and 18663929802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 192411600 + ... + 192411696.

Almost surely, 2^18663929856 is an apocalyptic number.

18663929856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18663929856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32429058480).

18663929856 is an abundant number, since it is smaller than the sum of its proper divisors (46194187104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18663929856 is a wasteful number, since it uses less digits than its factorization.

18663929856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 222 (or 199 counting only the distinct ones).

The product of its digits is 33592320, while the sum is 63.

The spelling of 18663929856 in words is "eighteen billion, six hundred sixty-three million, nine hundred twenty-nine thousand, eight hundred fifty-six".