12221232121 has 4 divisors (see below), whose sum is σ = 13967122432. Its totient is φ = 10475341812.

The previous prime is 12221232097. The next prime is 12221232197. The reversal of 12221232121 is 12123212221.

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 not a de Polignac number, because 12221232121 - 2¹⁹ = 12220707833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12221232721) 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, 872945145 + ... + 872945158.

It is an arithmetic number, because the mean of its divisors is an integer number (3491780608).

Almost surely, 2^12221232121 is an apocalyptic number.

It is an amenable number.

12221232121 is a deficient number, since it is larger than the sum of its proper divisors (1745890311).

12221232121 is an equidigital number, since it uses as much as digits as its factorization.

12221232121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1745890310.

The product of its digits is 192, while the sum is 19.

Adding to 12221232121 its reverse (12123212221), we get a palindrome (24344444342).

The spelling of 12221232121 in words is "twelve billion, two hundred twenty-one million, two hundred thirty-two thousand, one hundred twenty-one".