21842444 has 12 divisors (see below), whose sum is σ = 41164704. Its totient is φ = 10081104.

The previous prime is 21842441. The next prime is 21842477. The reversal of 21842444 is 44424812.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21842441) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209972 + ... + 210075.

It is an arithmetic number, because the mean of its divisors is an integer number (3430392).

Almost surely, 2^21842444 is an apocalyptic number.

It is an amenable number.

21842444 is a deficient number, since it is larger than the sum of its proper divisors (19322260).

21842444 is a wasteful number, since it uses less digits than its factorization.

21842444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 420064 (or 420062 counting only the distinct ones).

The product of its digits is 8192, while the sum is 29.

The square root of 21842444 is about 4673.5900547652. The cubic root of 21842444 is about 279.5334236353.

The spelling of 21842444 in words is "twenty-one million, eight hundred forty-two thousand, four hundred forty-four".