21044136 has 32 divisors (see below), whose sum is σ = 53127360. Its totient is φ = 6945792.

The previous prime is 21044129. The next prime is 21044197. The reversal of 21044136 is 63144012.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1785 + ... + 6728.

It is an arithmetic number, because the mean of its divisors is an integer number (1660230).

Almost surely, 2^21044136 is an apocalyptic number.

It is an amenable number.

21044136 is an abundant number, since it is smaller than the sum of its proper divisors (32083224).

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

21044136 is a wasteful number, since it uses less digits than its factorization.

21044136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8625 (or 8621 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 21044136 is about 4587.3887997422. The cubic root of 21044136 is about 276.0855647331.

Adding to 21044136 its reverse (63144012), we get a palindrome (84188148).

The spelling of 21044136 in words is "twenty-one million, forty-four thousand, one hundred thirty-six".