18805192021 has 48 divisors (see below), whose sum is σ = 25080200640. Its totient is φ = 13925157120.

The previous prime is 18805192019. The next prime is 18805192027. The reversal of 18805192021 is 12029150881.

It is not a de Polignac number, because 18805192021 - 2¹ = 18805192019 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18805192027) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 846585 + ... + 868513.

It is an arithmetic number, because the mean of its divisors is an integer number (522504180).

Almost surely, 2^18805192021 is an apocalyptic number.

18805192021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18805192021 is a deficient number, since it is larger than the sum of its proper divisors (6275008619).

18805192021 is a wasteful number, since it uses less digits than its factorization.

18805192021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22034 (or 22027 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 37.

The spelling of 18805192021 in words is "eighteen billion, eight hundred five million, one hundred ninety-two thousand, twenty-one".