21874864 has 30 divisors (see below), whose sum is σ = 46589900. Its totient is φ = 9942240.

The previous prime is 21874843. The next prime is 21874891. The reversal of 21874864 is 46847812.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3714 + ... + 7585.

Almost surely, 2^21874864 is an apocalyptic number.

It is an amenable number.

21874864 is an abundant number, since it is smaller than the sum of its proper divisors (24715036).

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

21874864 is a wasteful number, since it uses less digits than its factorization.

21874864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11329 (or 11312 counting only the distinct ones).

The product of its digits is 86016, while the sum is 40.

The square root of 21874864 is about 4677.0571944333. The cubic root of 21874864 is about 279.6716559317.

It can be divided in two parts, 218748 and 64, that added together give a palindrome (218812).

The spelling of 21874864 in words is "twenty-one million, eight hundred seventy-four thousand, eight hundred sixty-four".