22122122221 has 4 divisors (see below), whose sum is σ = 22122527872. Its totient is φ = 22121716572.

The previous prime is 22122122203. The next prime is 22122122251. The reversal of 22122122221 is 12222122122.

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 a de Polignac number, because none of the positive numbers 2^k-22122122221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (22122122251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 105435 + ... + 235288.

It is an arithmetic number, because the mean of its divisors is an integer number (5530631968).

Almost surely, 2^22122122221 is an apocalyptic number.

It is an amenable number.

22122122221 is a deficient number, since it is larger than the sum of its proper divisors (405651).

22122122221 is an equidigital number, since it uses as much as digits as its factorization.

22122122221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405650.

The product of its digits is 256, while the sum is 19.

Adding to 22122122221 its reverse (12222122122), we get a palindrome (34344244343).

Subtracting from 22122122221 its reverse (12222122122), we obtain a palindrome (9900000099).

The spelling of 22122122221 in words is "twenty-two billion, one hundred twenty-two million, one hundred twenty-two thousand, two hundred twenty-one".