21888538868 has 24 divisors (see below), whose sum is σ = 43813839552. Its totient is φ = 9372924864.

The previous prime is 21888538843. The next prime is 21888538883. The reversal of 21888538868 is 86883588812.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 294230 + ... + 361037.

It is an arithmetic number, because the mean of its divisors is an integer number (1825576648).

Almost surely, 2^21888538868 is an apocalyptic number.

21888538868 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21888538868 is an abundant number, since it is smaller than the sum of its proper divisors (21925300684).

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

21888538868 is a wasteful number, since it uses less digits than its factorization.

21888538868 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 656471 (or 656469 counting only the distinct ones).

The product of its digits is 47185920, while the sum is 65.

The spelling of 21888538868 in words is "twenty-one billion, eight hundred eighty-eight million, five hundred thirty-eight thousand, eight hundred sixty-eight".