21433872 has 40 divisors (see below), whose sum is σ = 58630176. Its totient is φ = 6724096.

The previous prime is 21433859. The next prime is 21433873. The reversal of 21433872 is 27833412.

It is not an unprimeable number, because it can be changed into a prime (21433873) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12318 + ... + 13949.

Almost surely, 2^21433872 is an apocalyptic number.

It is an amenable number.

21433872 is an abundant number, since it is smaller than the sum of its proper divisors (37196304).

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

21433872 is a wasteful number, since it uses less digits than its factorization.

21433872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26295 (or 26289 counting only the distinct ones).

The product of its digits is 8064, while the sum is 30.

The square root of 21433872 is about 4629.6729906118. The cubic root of 21433872 is about 277.7795122144.

The spelling of 21433872 in words is "twenty-one million, four hundred thirty-three thousand, eight hundred seventy-two".