22238721 has 12 divisors (see below), whose sum is σ = 33813520. Its totient is φ = 14045400.

The previous prime is 22238681. The next prime is 22238729. The reversal of 22238721 is 12783222.

It is a happy number.

It is not a de Polignac number, because 22238721 - 2¹¹ = 22236673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22238729) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64855 + ... + 65196.

Almost surely, 2^22238721 is an apocalyptic number.

It is an amenable number.

22238721 is a deficient number, since it is larger than the sum of its proper divisors (11574799).

22238721 is a wasteful number, since it uses less digits than its factorization.

22238721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130076 (or 130073 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 22238721 is about 4715.7948428658. The cubic root of 22238721 is about 281.2137825956.

The spelling of 22238721 in words is "twenty-two million, two hundred thirty-eight thousand, seven hundred twenty-one".