21131224032 has 24 divisors (see below), whose sum is σ = 55469463336. Its totient is φ = 7043741312.

The previous prime is 21131223973. The next prime is 21131224039. The reversal of 21131224032 is 23042213112.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21131224039) 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 3 ways as a sum of consecutive naturals, for example, 110058363 + ... + 110058554.

It is an arithmetic number, because the mean of its divisors is an integer number (2311227639).

Almost surely, 2^21131224032 is an apocalyptic number.

It is an amenable number.

21131224032 is an abundant number, since it is smaller than the sum of its proper divisors (34338239304).

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

21131224032 is a wasteful number, since it uses less digits than its factorization.

21131224032 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220116930 (or 220116922 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

Adding to 21131224032 its reverse (23042213112), we get a palindrome (44173437144).

The spelling of 21131224032 in words is "twenty-one billion, one hundred thirty-one million, two hundred twenty-four thousand, thirty-two".