21867264 has 54 divisors (see below), whose sum is σ = 63055356. Its totient is φ = 7288320.

The previous prime is 21867221. The next prime is 21867277. The reversal of 21867264 is 46276812.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2442 + ... + 7049.

Almost surely, 2^21867264 is an apocalyptic number.

21867264 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21867264 is an abundant number, since it is smaller than the sum of its proper divisors (41188092).

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

21867264 is an equidigital number, since it uses as much as digits as its factorization.

21867264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9513 (or 9496 counting only the distinct ones).

The product of its digits is 32256, while the sum is 36.

The square root of 21867264 is about 4676.2446471501. The cubic root of 21867264 is about 279.6392633374.

The spelling of 21867264 in words is "twenty-one million, eight hundred sixty-seven thousand, two hundred sixty-four".