21572832 has 24 divisors (see below), whose sum is σ = 56628936. Its totient is φ = 7190912.

The previous prime is 21572783. The next prime is 21572849. The reversal of 21572832 is 23827512.

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

It is a self number, because there is not a number n which added to its sum of digits gives 21572832.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 112263 + ... + 112454.

It is an arithmetic number, because the mean of its divisors is an integer number (2359539).

Almost surely, 2^21572832 is an apocalyptic number.

It is an amenable number.

21572832 is an abundant number, since it is smaller than the sum of its proper divisors (35056104).

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

21572832 is a wasteful number, since it uses less digits than its factorization.

21572832 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224730 (or 224722 counting only the distinct ones).

The product of its digits is 6720, while the sum is 30.

The square root of 21572832 is about 4644.6562843767. The cubic root of 21572832 is about 278.3785192833.

The spelling of 21572832 in words is "twenty-one million, five hundred seventy-two thousand, eight hundred thirty-two".