21943264 has 24 divisors (see below), whose sum is σ = 49372848. Its totient is φ = 9404160.

The previous prime is 21943261. The next prime is 21943267. The reversal of 21943264 is 46234912.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21943261) and next prime (21943267).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21943261) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 48757 + ... + 49204.

It is an arithmetic number, because the mean of its divisors is an integer number (2057202).

Almost surely, 2^21943264 is an apocalyptic number.

It is an amenable number.

21943264 is an abundant number, since it is smaller than the sum of its proper divisors (27429584).

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

21943264 is an equidigital number, since it uses as much as digits as its factorization.

21943264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97978 (or 97970 counting only the distinct ones).

The product of its digits is 10368, while the sum is 31.

The square root of 21943264 is about 4684.3637775049. The cubic root of 21943264 is about 279.9628522147.

The spelling of 21943264 in words is "twenty-one million, nine hundred forty-three thousand, two hundred sixty-four".