21865022 has 16 divisors (see below), whose sum is σ = 33530112. Its totient is φ = 10691160.

The previous prime is 21865007. The next prime is 21865037. The reversal of 21865022 is 22056812.

It is an interprime number because it is at equal distance from previous prime (21865007) and next prime (21865037).

It is a junction number, because it is equal to n+sod(n) for n = 21864982 and 21865000.

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, 17147 + ... + 18377.

It is an arithmetic number, because the mean of its divisors is an integer number (2095632).

Almost surely, 2^21865022 is an apocalyptic number.

21865022 is a deficient number, since it is larger than the sum of its proper divisors (11665090).

21865022 is a wasteful number, since it uses less digits than its factorization.

21865022 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1423.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 21865022 is about 4676.0049187314. The cubic root of 21865022 is about 279.6297060885.

The spelling of 21865022 in words is "twenty-one million, eight hundred sixty-five thousand, twenty-two".