21433844 has 12 divisors (see below), whose sum is σ = 37589664. Its totient is φ = 10693944.

The previous prime is 21433831. The next prime is 21433859. The reversal of 21433844 is 44833412.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3554 + ... + 7449.

It is an arithmetic number, because the mean of its divisors is an integer number (3132472).

Almost surely, 2^21433844 is an apocalyptic number.

It is an amenable number.

21433844 is a deficient number, since it is larger than the sum of its proper divisors (16155820).

21433844 is a wasteful number, since it uses less digits than its factorization.

21433844 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11494 (or 11492 counting only the distinct ones).

The product of its digits is 9216, while the sum is 29.

The square root of 21433844 is about 4629.6699666391. The cubic root of 21433844 is about 277.7793912558.

The spelling of 21433844 in words is "twenty-one million, four hundred thirty-three thousand, eight hundred forty-four".