21321235530 has 96 divisors (see below), whose sum is σ = 65701044864. Its totient is φ = 4873421376.

The previous prime is 21321235519. The next prime is 21321235531. The reversal of 21321235530 is 3553212312.

It is a happy number.

21321235530 is a `hidden beast` number, since 2 + 1 + 3 + 2 + 123 + 5 + 530 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 21321235494 and 21321235503.

It is not an unprimeable number, because it can be changed into a prime (21321235531) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 609717 + ... + 643736.

It is an arithmetic number, because the mean of its divisors is an integer number (684385884).

Almost surely, 2^21321235530 is an apocalyptic number.

21321235530 is an abundant number, since it is smaller than the sum of its proper divisors (44379809334).

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

21321235530 is a wasteful number, since it uses less digits than its factorization.

21321235530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1253482 (or 1253470 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 27.

Adding to 21321235530 its reverse (3553212312), we get a palindrome (24874447842).

The spelling of 21321235530 in words is "twenty-one billion, three hundred twenty-one million, two hundred thirty-five thousand, five hundred thirty".