21433431232 has 56 divisors (see below), whose sum is σ = 44861480000. Its totient is φ = 10132045056.

The previous prime is 21433431193. The next prime is 21433431247. The reversal of 21433431232 is 23213433412.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21433431232.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 589123 + ... + 624445.

Almost surely, 2^21433431232 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 21433431232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22430740000).

21433431232 is an abundant number, since it is smaller than the sum of its proper divisors (23428048768).

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

21433431232 is a wasteful number, since it uses less digits than its factorization.

21433431232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35853 (or 35843 counting only the distinct ones).

The product of its digits is 10368, while the sum is 28.

Adding to 21433431232 its reverse (23213433412), we get a palindrome (44646864644).

The spelling of 21433431232 in words is "twenty-one billion, four hundred thirty-three million, four hundred thirty-one thousand, two hundred thirty-two".