21889855 has 8 divisors (see below), whose sum is σ = 28288512. Its totient is φ = 16164768.

The previous prime is 21889841. The next prime is 21889871. The reversal of 21889855 is 55898812.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21889855 - 2⁵ = 21889823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 168319 + ... + 168448.

It is an arithmetic number, because the mean of its divisors is an integer number (3536064).

Almost surely, 2^21889855 is an apocalyptic number.

21889855 is a deficient number, since it is larger than the sum of its proper divisors (6398657).

21889855 is a wasteful number, since it uses less digits than its factorization.

21889855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 336785.

The product of its digits is 230400, while the sum is 46.

The square root of 21889855 is about 4678.6595302501. The cubic root of 21889855 is about 279.7355283354.

The spelling of 21889855 in words is "twenty-one million, eight hundred eighty-nine thousand, eight hundred fifty-five".