21164264 has 16 divisors (see below), whose sum is σ = 43290720. Its totient is φ = 9620080.

The previous prime is 21164239. The next prime is 21164281. The reversal of 21164264 is 46246112.

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 3 ways as a sum of consecutive naturals, for example, 120164 + ... + 120339.

It is an arithmetic number, because the mean of its divisors is an integer number (2705670).

Almost surely, 2^21164264 is an apocalyptic number.

It is an amenable number.

21164264 is an abundant number, since it is smaller than the sum of its proper divisors (22126456).

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

21164264 is a wasteful number, since it uses less digits than its factorization.

21164264 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240520 (or 240516 counting only the distinct ones).

The product of its digits is 2304, while the sum is 26.

The square root of 21164264 is about 4600.4634549141. The cubic root of 21164264 is about 276.6099023880.

The spelling of 21164264 in words is "twenty-one million, one hundred sixty-four thousand, two hundred sixty-four".