21859452 has 36 divisors (see below), whose sum is σ = 56752696. Its totient is φ = 7089120.

The previous prime is 21859451. The next prime is 21859457. The reversal of 21859452 is 25495812.

21859452 is a `hidden beast` number, since 2 + 18 + 594 + 52 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21859451) 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 11 ways as a sum of consecutive naturals, for example, 6874 + ... + 9537.

Almost surely, 2^21859452 is an apocalyptic number.

It is an amenable number.

21859452 is an abundant number, since it is smaller than the sum of its proper divisors (34893244).

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

21859452 is a wasteful number, since it uses less digits than its factorization.

21859452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16458 (or 16453 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

The square root of 21859452 is about 4675.4092868967. The cubic root of 21859452 is about 279.6059593368.

The spelling of 21859452 in words is "twenty-one million, eight hundred fifty-nine thousand, four hundred fifty-two".