21731452 has 12 divisors (see below), whose sum is σ = 38189536. Its totient is φ = 10820160.

The previous prime is 21731449. The next prime is 21731453. The reversal of 21731452 is 25413712.

It is a happy number.

It is a hoax number, since the sum of its digits (25) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21731453) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10308 + ... + 12235.

Almost surely, 2^21731452 is an apocalyptic number.

It is an amenable number.

21731452 is a deficient number, since it is larger than the sum of its proper divisors (16458084).

21731452 is a wasteful number, since it uses less digits than its factorization.

21731452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22788 (or 22786 counting only the distinct ones).

The product of its digits is 1680, while the sum is 25.

The square root of 21731452 is about 4661.7005480833. The cubic root of 21731452 is about 279.0591379545.

The spelling of 21731452 in words is "twenty-one million, seven hundred thirty-one thousand, four hundred fifty-two".