21432884 has 12 divisors (see below), whose sum is σ = 40917408. Its totient is φ = 9742200.

The previous prime is 21432881. The next prime is 21432913. The reversal of 21432884 is 48823412.

It is a self number, because there is not a number n which added to its sum of digits gives 21432884.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21432881) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243512 + ... + 243599.

It is an arithmetic number, because the mean of its divisors is an integer number (3409784).

Almost surely, 2^21432884 is an apocalyptic number.

It is an amenable number.

21432884 is a deficient number, since it is larger than the sum of its proper divisors (19484524).

21432884 is a wasteful number, since it uses less digits than its factorization.

21432884 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487126 (or 487124 counting only the distinct ones).

The product of its digits is 12288, while the sum is 32.

The square root of 21432884 is about 4629.5662863815. The cubic root of 21432884 is about 277.7752440421.

It can be divided in two parts, 214328 and 84, that added together give a palindrome (214412).

The spelling of 21432884 in words is "twenty-one million, four hundred thirty-two thousand, eight hundred eighty-four".