21056044 has 24 divisors (see below), whose sum is σ = 37691136. Its totient is φ = 10290000.

The previous prime is 21056039. The next prime is 21056051. The reversal of 21056044 is 44065012.

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, 42639 + ... + 43129.

It is an arithmetic number, because the mean of its divisors is an integer number (1570464).

Almost surely, 2^21056044 is an apocalyptic number.

It is an amenable number.

21056044 is a deficient number, since it is larger than the sum of its proper divisors (16635092).

21056044 is a wasteful number, since it uses less digits than its factorization.

21056044 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717 (or 715 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

The square root of 21056044 is about 4588.6865223068. The cubic root of 21056044 is about 276.1376300208.

The spelling of 21056044 in words is "twenty-one million, fifty-six thousand, forty-four".