22188121 has 4 divisors (see below), whose sum is σ = 22321152. Its totient is φ = 22055092.

The previous prime is 22188119. The next prime is 22188163. The reversal of 22188121 is 12188122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 22188121 - 2¹ = 22188119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22188191) 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, 66265 + ... + 66598.

It is an arithmetic number, because the mean of its divisors is an integer number (5580288).

Almost surely, 2^22188121 is an apocalyptic number.

It is an amenable number.

22188121 is a deficient number, since it is larger than the sum of its proper divisors (133031).

22188121 is a wasteful number, since it uses less digits than its factorization.

22188121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133030.

The product of its digits is 512, while the sum is 25.

The square root of 22188121 is about 4710.4268384086. The cubic root of 22188121 is about 281.0003377191. Note that the first 3 decimals are identical.

Subtracting from 22188121 its reverse (12188122), we obtain a palindrome (9999999).

The spelling of 22188121 in words is "twenty-two million, one hundred eighty-eight thousand, one hundred twenty-one".