21539722884 has 48 divisors (see below), whose sum is σ = 51455756352. Its totient is φ = 7009172352.

The previous prime is 21539722877. The next prime is 21539722907. The reversal of 21539722884 is 48822793512.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1049182 + ... + 1069514.

It is an arithmetic number, because the mean of its divisors is an integer number (1071994924).

Almost surely, 2^21539722884 is an apocalyptic number.

It is an amenable number.

21539722884 is an abundant number, since it is smaller than the sum of its proper divisors (29916033468).

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

21539722884 is a wasteful number, since it uses less digits than its factorization.

21539722884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22436 (or 22434 counting only the distinct ones).

The product of its digits is 1935360, while the sum is 51.

The spelling of 21539722884 in words is "twenty-one billion, five hundred thirty-nine million, seven hundred twenty-two thousand, eight hundred eighty-four".