21397024000 has 288 divisors, whose sum is σ = 58887803520. Its totient is φ = 7682048000.

The previous prime is 21397023997. The next prime is 21397024003. The reversal of 21397024000 is 42079312.

It is an interprime number because it is at equal distance from previous prime (21397023997) and next prime (21397024003).

It is a self number, because there is not a number n which added to its sum of digits gives 21397024000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21397024003) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 31327659 + ... + 31328341.

It is an arithmetic number, because the mean of its divisors is an integer number (204471540).

Almost surely, 2^21397024000 is an apocalyptic number.

21397024000 is a gapful number since it is divisible by the number (20) 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 21397024000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29443901760).

21397024000 is an abundant number, since it is smaller than the sum of its proper divisors (37490779520).

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

21397024000 is an equidigital number, since it uses as much as digits as its factorization.

21397024000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 814 (or 790 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 28.

The spelling of 21397024000 in words is "twenty-one billion, three hundred ninety-seven million, twenty-four thousand".