21944223 has 16 divisors (see below), whose sum is σ = 37154560. Its totient is φ = 12539448.

The previous prime is 21944189. The next prime is 21944227. The reversal of 21944223 is 32244912.

21944223 is a `hidden beast` number, since 219 + 442 + 2 + 3 = 666.

It is not a de Polignac number, because 21944223 - 2⁹ = 21943711 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21944227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 57865 + ... + 58242.

It is an arithmetic number, because the mean of its divisors is an integer number (2322160).

Almost surely, 2^21944223 is an apocalyptic number.

21944223 is a deficient number, since it is larger than the sum of its proper divisors (15210337).

21944223 is a wasteful number, since it uses less digits than its factorization.

21944223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116123 (or 116117 counting only the distinct ones).

The product of its digits is 3456, while the sum is 27.

The square root of 21944223 is about 4684.4661382061. The cubic root of 21944223 is about 279.9669306183.

The spelling of 21944223 in words is "twenty-one million, nine hundred forty-four thousand, two hundred twenty-three".