21808688832 has 560 divisors, whose sum is σ = 79544509440. Its totient is φ = 5768921088.

The previous prime is 21808688827. The next prime is 21808688843. The reversal of 21808688832 is 23888680812.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 32404848 + ... + 32405520.

Almost surely, 2^21808688832 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 21808688832, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39772254720).

21808688832 is an abundant number, since it is smaller than the sum of its proper divisors (57735820608).

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

21808688832 is a wasteful number, since it uses less digits than its factorization.

21808688832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 770 (or 751 counting only the distinct ones).

The product of its (nonzero) digits is 2359296, while the sum is 54.

The spelling of 21808688832 in words is "twenty-one billion, eight hundred eight million, six hundred eighty-eight thousand, eight hundred thirty-two".