21333264 has 20 divisors (see below), whose sum is σ = 55111056. Its totient is φ = 7111072.

The previous prime is 21333251. The next prime is 21333271. The reversal of 21333264 is 46233312.

It is a Harshad number since it is a multiple of its sum of digits (24).

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 222174 + ... + 222269.

Almost surely, 2^21333264 is an apocalyptic number.

21333264 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21333264 is an abundant number, since it is smaller than the sum of its proper divisors (33777792).

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

21333264 is a wasteful number, since it uses less digits than its factorization.

21333264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 444454 (or 444448 counting only the distinct ones).

The product of its digits is 2592, while the sum is 24.

The square root of 21333264 is about 4618.7946479574. The cubic root of 21333264 is about 277.3442092834.

Adding to 21333264 its reverse (46233312), we get a palindrome (67566576).

The spelling of 21333264 in words is "twenty-one million, three hundred thirty-three thousand, two hundred sixty-four".