12111221231 has 2 divisors, whose sum is σ = 12111221232. Its totient is φ = 12111221230.

The previous prime is 12111221219. The next prime is 12111221233. The reversal of 12111221231 is 13212211121.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (13212211121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12111221231 - 2²² = 12107026927 is a prime.

It is a super-2 number, since 2×12111221231² (a number of 21 digits) contains 22 as substring.

Together with 12111221233, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12111221233) 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 as a sum of consecutive naturals, namely, 6055610615 + 6055610616.

It is an arithmetic number, because the mean of its divisors is an integer number (6055610616).

Almost surely, 2^12111221231 is an apocalyptic number.

12111221231 is a deficient number, since it is larger than the sum of its proper divisors (1).

12111221231 is an equidigital number, since it uses as much as digits as its factorization.

12111221231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 17.

Adding to 12111221231 its reverse (13212211121), we get a palindrome (25323432352).

The spelling of 12111221231 in words is "twelve billion, one hundred eleven million, two hundred twenty-one thousand, two hundred thirty-one".