21266924 has 24 divisors (see below), whose sum is σ = 43051008. Its totient is φ = 9003600.

The previous prime is 21266911. The next prime is 21266929. The reversal of 21266924 is 42966212.

It is a super-4 number, since 4×21266924⁴ (a number of 30 digits) contains 4444 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21266929) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2252 + ... + 6899.

It is an arithmetic number, because the mean of its divisors is an integer number (1793792).

Almost surely, 2^21266924 is an apocalyptic number.

It is an amenable number.

21266924 is an abundant number, since it is smaller than the sum of its proper divisors (21784084).

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

21266924 is a wasteful number, since it uses less digits than its factorization.

21266924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9245 (or 9243 counting only the distinct ones).

The product of its digits is 10368, while the sum is 32.

The square root of 21266924 is about 4611.6075288342. The cubic root of 21266924 is about 277.0564252285.

The spelling of 21266924 in words is "twenty-one million, two hundred sixty-six thousand, nine hundred twenty-four".