21459815088 has 160 divisors (see below), whose sum is σ = 61904966400. Its totient is φ = 6366117888.

The previous prime is 21459815053. The next prime is 21459815119. The reversal of 21459815088 is 88051895412.

It is a super-2 number, since 2×21459815088² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a self number, because there is not a number n which added to its sum of digits gives 21459815088.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11456520 + ... + 11458392.

It is an arithmetic number, because the mean of its divisors is an integer number (386906040).

Almost surely, 2^21459815088 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 21459815088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30952483200).

21459815088 is an abundant number, since it is smaller than the sum of its proper divisors (40445151312).

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

21459815088 is a wasteful number, since it uses less digits than its factorization.

21459815088 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2659 (or 2653 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 51.

The spelling of 21459815088 in words is "twenty-one billion, four hundred fifty-nine million, eight hundred fifteen thousand, eighty-eight".