21373264 has 20 divisors (see below), whose sum is σ = 45175680. Its totient is φ = 9715040.

The previous prime is 21373249. The next prime is 21373277. The reversal of 21373264 is 46237312.

It is a super-4 number, since 4×21373264⁴ (a number of 30 digits) contains 4444 as substring.

It is a congruent number.

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, 60544 + ... + 60895.

It is an arithmetic number, because the mean of its divisors is an integer number (2258784).

Almost surely, 2^21373264 is an apocalyptic number.

It is an amenable number.

21373264 is an abundant number, since it is smaller than the sum of its proper divisors (23802416).

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

21373264 is a wasteful number, since it uses less digits than its factorization.

21373264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121458 (or 121452 counting only the distinct ones).

The product of its digits is 6048, while the sum is 28.

The square root of 21373264 is about 4623.1227541565. The cubic root of 21373264 is about 277.5174417520.

The spelling of 21373264 in words is "twenty-one million, three hundred seventy-three thousand, two hundred sixty-four".