12102222221 has 4 divisors (see below), whose sum is σ = 12111700572. Its totient is φ = 12092743872.

The previous prime is 12102222193. The next prime is 12102222227. The reversal of 12102222221 is 12222220121.

It is a happy number.

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 6890826121 + 5211396100 = 83011^2 + 72190^2 .

It is a cyclic number.

It is not a de Polignac number, because 12102222221 - 2²⁶ = 12035113357 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 12102222221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12102222227) 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, 4737260 + ... + 4739813.

It is an arithmetic number, because the mean of its divisors is an integer number (3027925143).

Almost surely, 2^12102222221 is an apocalyptic number.

It is an amenable number.

12102222221 is a deficient number, since it is larger than the sum of its proper divisors (9478351).

12102222221 is an equidigital number, since it uses as much as digits as its factorization.

12102222221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9478350.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 12102222221 its reverse (12222220121), we get a palindrome (24324442342).

It can be divided in two parts, 121022 and 22221, that multiplied together give a palindrome (2689229862).

The spelling of 12102222221 in words is "twelve billion, one hundred two million, two hundred twenty-two thousand, two hundred twenty-one".