21226044 has 24 divisors (see below), whose sum is σ = 56603008. Its totient is φ = 6064560.

The previous prime is 21226039. The next prime is 21226063. The reversal of 21226044 is 44062212.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 21226044.

It is a congruent number.

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, 126262 + ... + 126429.

Almost surely, 2^21226044 is an apocalyptic number.

It is an amenable number.

21226044 is an abundant number, since it is smaller than the sum of its proper divisors (35376964).

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

21226044 is a wasteful number, since it uses less digits than its factorization.

21226044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252705 (or 252703 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 21226044 is about 4607.1731028908. The cubic root of 21226044 is about 276.8787889526.

Adding to 21226044 its reverse (44062212), we get a palindrome (65288256).

The spelling of 21226044 in words is "twenty-one million, two hundred twenty-six thousand, forty-four".