21892857 has 12 divisors (see below), whose sum is σ = 33956496. Its totient is φ = 12510120.

The previous prime is 21892847. The next prime is 21892867. The reversal of 21892857 is 75829812.

It is an interprime number because it is at equal distance from previous prime (21892847) and next prime (21892867).

It is not a de Polignac number, because 21892857 - 2⁸ = 21892601 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21892817) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 74319 + ... + 74612.

It is an arithmetic number, because the mean of its divisors is an integer number (2829708).

Almost surely, 2^21892857 is an apocalyptic number.

It is an amenable number.

21892857 is a deficient number, since it is larger than the sum of its proper divisors (12063639).

21892857 is a wasteful number, since it uses less digits than its factorization.

21892857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148948 (or 148941 counting only the distinct ones).

The product of its digits is 80640, while the sum is 42.

The square root of 21892857 is about 4678.9803376377. The cubic root of 21892857 is about 279.7483155020.

The spelling of 21892857 in words is "twenty-one million, eight hundred ninety-two thousand, eight hundred fifty-seven".