21893856 has 24 divisors (see below), whose sum is σ = 57471624. Its totient is φ = 7297920.

The previous prime is 21893831. The next prime is 21893887. The reversal of 21893856 is 65839812.

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

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, 113935 + ... + 114126.

It is an arithmetic number, because the mean of its divisors is an integer number (2394651).

Almost surely, 2^21893856 is an apocalyptic number.

It is an amenable number.

21893856 is an abundant number, since it is smaller than the sum of its proper divisors (35577768).

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

21893856 is a wasteful number, since it uses less digits than its factorization.

21893856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228074 (or 228066 counting only the distinct ones).

The product of its digits is 103680, while the sum is 42.

The square root of 21893856 is about 4679.0870904483. The cubic root of 21893856 is about 279.7525705324.

The spelling of 21893856 in words is "twenty-one million, eight hundred ninety-three thousand, eight hundred fifty-six".