21112806384 has 160 divisors (see below), whose sum is σ = 64873824000. Its totient is φ = 6554048256.

The previous prime is 21112806353. The next prime is 21112806389. The reversal of 21112806384 is 48360821112.

21112806384 is a `hidden beast` number, since 2 + 1 + 1 + 12 + 8 + 0 + 638 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21112806389) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 462474 + ... + 506070.

It is an arithmetic number, because the mean of its divisors is an integer number (405461400).

Almost surely, 2^21112806384 is an apocalyptic number.

21112806384 is a gapful number since it is divisible by the number (24) 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 21112806384, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32436912000).

21112806384 is an abundant number, since it is smaller than the sum of its proper divisors (43761017616).

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

21112806384 is a wasteful number, since it uses less digits than its factorization.

21112806384 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43692 (or 43680 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The spelling of 21112806384 in words is "twenty-one billion, one hundred twelve million, eight hundred six thousand, three hundred eighty-four".