21422944 has 24 divisors (see below), whose sum is σ = 43160040. Its totient is φ = 10461696.

The previous prime is 21422939. The next prime is 21422993. The reversal of 21422944 is 44922412.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6409 + ... + 9160.

It is an arithmetic number, because the mean of its divisors is an integer number (1798335).

Almost surely, 2^21422944 is an apocalyptic number.

It is an amenable number.

21422944 is an abundant number, since it is smaller than the sum of its proper divisors (21737096).

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

21422944 is a wasteful number, since it uses less digits than its factorization.

21422944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15622 (or 15614 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 21422944 is about 4628.4926271952. The cubic root of 21422944 is about 277.7322958186.

It can be divided in two parts, 21422 and 944, that added together give a triangular number (22366 = T₂₁₁).

The spelling of 21422944 in words is "twenty-one million, four hundred twenty-two thousand, nine hundred forty-four".