22221222121 has 12 divisors (see below), whose sum is σ = 27369717588. Its totient is φ = 17926363392.

The previous prime is 22221222113. The next prime is 22221222137. The reversal of 22221222121 is 12122212222.

It can be written as a sum of positive squares in 2 ways, for example, as 19122741225 + 3098480896 = 138285^2 + 55664^2 .

It is not a de Polignac number, because 22221222121 - 2³ = 22221222113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22221222161) 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 11 ways as a sum of consecutive naturals, for example, 13337236 + ... + 13338901.

It is an arithmetic number, because the mean of its divisors is an integer number (2280809799).

Almost surely, 2^22221222121 is an apocalyptic number.

It is an amenable number.

22221222121 is a deficient number, since it is larger than the sum of its proper divisors (5148495467).

22221222121 is a wasteful number, since it uses less digits than its factorization.

22221222121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26676168 (or 26676161 counting only the distinct ones).

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

Adding to 22221222121 its reverse (12122212222), we get a palindrome (34343434343).

The spelling of 22221222121 in words is "twenty-two billion, two hundred twenty-one million, two hundred twenty-two thousand, one hundred twenty-one".