18856981836 has 216 divisors, whose sum is σ = 60682671504. Its totient is φ = 4882268160.

The previous prime is 18856981807. The next prime is 18856981841. The reversal of 18856981836 is 63818965881.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 6848236 + ... + 6850988.

It is an arithmetic number, because the mean of its divisors is an integer number (280938294).

Almost surely, 2^18856981836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18856981836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30341335752).

18856981836 is an abundant number, since it is smaller than the sum of its proper divisors (41825689668).

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

18856981836 is a wasteful number, since it uses less digits than its factorization.

18856981836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3141 (or 3129 counting only the distinct ones).

The product of its digits is 19906560, while the sum is 63.

The spelling of 18856981836 in words is "eighteen billion, eight hundred fifty-six million, nine hundred eighty-one thousand, eight hundred thirty-six".