21282864 has 40 divisors (see below), whose sum is σ = 56758272. Its totient is φ = 6864960.

The previous prime is 21282857. The next prime is 21282871. The reversal of 21282864 is 46828212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21282857) and next prime (21282871).

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5664 + ... + 8639.

Almost surely, 2^21282864 is an apocalyptic number.

21282864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21282864 is an abundant number, since it is smaller than the sum of its proper divisors (35475408).

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

21282864 is a wasteful number, since it uses less digits than its factorization.

21282864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14345 (or 14339 counting only the distinct ones).

The product of its digits is 12288, while the sum is 33.

The square root of 21282864 is about 4613.3354527933. The cubic root of 21282864 is about 277.1256277848.

The spelling of 21282864 in words is "twenty-one million, two hundred eighty-two thousand, eight hundred sixty-four".