21854856 has 16 divisors (see below), whose sum is σ = 54637200. Its totient is φ = 7284944.

The previous prime is 21854837. The next prime is 21854867. The reversal of 21854856 is 65845812.

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, 455286 + ... + 455333.

It is an arithmetic number, because the mean of its divisors is an integer number (3414825).

Almost surely, 2^21854856 is an apocalyptic number.

It is an amenable number.

21854856 is an abundant number, since it is smaller than the sum of its proper divisors (32782344).

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

21854856 is a wasteful number, since it uses less digits than its factorization.

21854856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 910628 (or 910624 counting only the distinct ones).

The product of its digits is 76800, while the sum is 39.

The square root of 21854856 is about 4674.9177532872. The cubic root of 21854856 is about 279.5863620316.

The spelling of 21854856 in words is "twenty-one million, eight hundred fifty-four thousand, eight hundred fifty-six".