21525231432 has 32 divisors (see below), whose sum is σ = 54550248480. Its totient is φ = 7076787840.

The previous prime is 21525231401. The next prime is 21525231439. The reversal of 21525231432 is 23413252512.

It is a self number, because there is not a number n which added to its sum of digits gives 21525231432.

It is not an unprimeable number, because it can be changed into a prime (21525231439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6141294 + ... + 6144797.

It is an arithmetic number, because the mean of its divisors is an integer number (1704695265).

Almost surely, 2^21525231432 is an apocalyptic number.

It is an amenable number.

21525231432 is an abundant number, since it is smaller than the sum of its proper divisors (33025017048).

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

21525231432 is a wasteful number, since it uses less digits than its factorization.

21525231432 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12286173 (or 12286169 counting only the distinct ones).

The product of its digits is 14400, while the sum is 30.

Adding to 21525231432 its reverse (23413252512), we get a palindrome (44938483944).

The spelling of 21525231432 in words is "twenty-one billion, five hundred twenty-five million, two hundred thirty-one thousand, four hundred thirty-two".