22142221 has 4 divisors (see below), whose sum is σ = 22391100. Its totient is φ = 21893344.

The previous prime is 22142213. The next prime is 22142231. The reversal of 22142221 is 12224122.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 8555625 + 13586596 = 2925^2 + 3686^2 .

It is a cyclic number.

It is not a de Polignac number, because 22142221 - 2³ = 22142213 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 22142195 and 22142204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22142231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124306 + ... + 124483.

It is an arithmetic number, because the mean of its divisors is an integer number (5597775).

Almost surely, 2^22142221 is an apocalyptic number.

It is an amenable number.

22142221 is a deficient number, since it is larger than the sum of its proper divisors (248879).

22142221 is an equidigital number, since it uses as much as digits as its factorization.

22142221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 248878.

The product of its digits is 128, while the sum is 16.

The square root of 22142221 is about 4705.5521461355. The cubic root of 22142221 is about 280.8064378751.

Adding to 22142221 its reverse (12224122), we get a palindrome (34366343).

The spelling of 22142221 in words is "twenty-two million, one hundred forty-two thousand, two hundred twenty-one".