21874665 has 32 divisors (see below), whose sum is σ = 37445760. Its totient is φ = 10865664.

The previous prime is 21874627. The next prime is 21874673. The reversal of 21874665 is 56647812.

It is not a de Polignac number, because 21874665 - 2⁷ = 21874537 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27402 + ... + 28188.

It is an arithmetic number, because the mean of its divisors is an integer number (1170180).

Almost surely, 2^21874665 is an apocalyptic number.

It is an amenable number.

21874665 is a deficient number, since it is larger than the sum of its proper divisors (15571095).

21874665 is a wasteful number, since it uses less digits than its factorization.

21874665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 921.

The product of its digits is 80640, while the sum is 39.

The square root of 21874665 is about 4677.0359203239. The cubic root of 21874665 is about 279.6708078529.

The spelling of 21874665 in words is "twenty-one million, eight hundred seventy-four thousand, six hundred sixty-five".