21852855 has 16 divisors (see below), whose sum is σ = 38849760. Its totient is φ = 11654784.

The previous prime is 21852851. The next prime is 21852881. The reversal of 21852855 is 55825812.

It is not a de Polignac number, because 21852855 - 2² = 21852851 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21852851) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80802 + ... + 81071.

It is an arithmetic number, because the mean of its divisors is an integer number (2428110).

Almost surely, 2^21852855 is an apocalyptic number.

21852855 is a deficient number, since it is larger than the sum of its proper divisors (16996905).

21852855 is a wasteful number, since it uses less digits than its factorization.

21852855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161887 (or 161881 counting only the distinct ones).

The product of its digits is 32000, while the sum is 36.

The square root of 21852855 is about 4674.7037339280. The cubic root of 21852855 is about 279.5778289259.

The spelling of 21852855 in words is "twenty-one million, eight hundred fifty-two thousand, eight hundred fifty-five".