22918221 has 40 divisors (see below), whose sum is σ = 35939904. Its totient is φ = 14541120.

The previous prime is 22918219. The next prime is 22918253. The reversal of 22918221 is 12281922.

It is not a de Polignac number, because 22918221 - 2¹ = 22918219 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22918271) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 222456 + ... + 222558.

Almost surely, 2^22918221 is an apocalyptic number.

It is an amenable number.

22918221 is a deficient number, since it is larger than the sum of its proper divisors (13021683).

22918221 is a wasteful number, since it uses less digits than its factorization.

22918221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223 (or 214 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 22918221 is about 4787.2978808510. The cubic root of 22918221 is about 284.0492417757.

The spelling of 22918221 in words is "twenty-two million, nine hundred eighteen thousand, two hundred twenty-one".