22012122222221 has 4 divisors (see below), whose sum is σ = 22020559220700. Its totient is φ = 22003685223744.

The previous prime is 22012122222191. The next prime is 22012122222263. The reversal of 22012122222221 is 12222222121022.

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 7082592206596 + 14929530015625 = 2661314^2 + 3863875^2 .

It is a cyclic number.

It is not a de Polignac number, because 22012122222221 - 2³⁸ = 21737244315277 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 (22012122222271) 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, 4218495326 + ... + 4218500543.

It is an arithmetic number, because the mean of its divisors is an integer number (5505139805175).

Almost surely, 2^{22012122222221} is an apocalyptic number.

It is an amenable number.

22012122222221 is a deficient number, since it is larger than the sum of its proper divisors (8436998479).

22012122222221 is an equidigital number, since it uses as much as digits as its factorization.

22012122222221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8436998478.

The product of its (nonzero) digits is 1024, while the sum is 23.

Adding to 22012122222221 its reverse (12222222121022), we get a palindrome (34234344343243).

The spelling of 22012122222221 in words is "twenty-two trillion, twelve billion, one hundred twenty-two million, two hundred twenty-two thousand, two hundred twenty-one".