21524367788 has 72 divisors (see below), whose sum is σ = 48106089360. Its totient is φ = 8332571520.

The previous prime is 21524367757. The next prime is 21524367841. The reversal of 21524367788 is 88776342512.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 306698 + ... + 370286.

It is an arithmetic number, because the mean of its divisors is an integer number (668140130).

Almost surely, 2^21524367788 is an apocalyptic number.

21524367788 is a gapful number since it is divisible by the number (28) 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 21524367788, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24053044680).

21524367788 is an abundant number, since it is smaller than the sum of its proper divisors (26581721572).

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

21524367788 is a wasteful number, since it uses less digits than its factorization.

21524367788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63775 (or 63766 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 53.

The spelling of 21524367788 in words is "twenty-one billion, five hundred twenty-four million, three hundred sixty-seven thousand, seven hundred eighty-eight".