12312211221 has 8 divisors (see below), whose sum is σ = 18240312960. Its totient is φ = 8208140796.

The previous prime is 12312211207. The next prime is 12312211231. The reversal of 12312211221 is 12211221321.

12312211221 is a `hidden beast` number, since 1 + 231 + 2 + 211 + 221 = 666.

It is not a de Polignac number, because 12312211221 - 2²⁶ = 12245102357 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12312211194 and 12312211203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12312211231) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 228003885 + ... + 228003938.

It is an arithmetic number, because the mean of its divisors is an integer number (2280039120).

Almost surely, 2^12312211221 is an apocalyptic number.

It is an amenable number.

12312211221 is a deficient number, since it is larger than the sum of its proper divisors (5928101739).

12312211221 is an equidigital number, since it uses as much as digits as its factorization.

12312211221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456007832 (or 456007826 counting only the distinct ones).

The product of its digits is 96, while the sum is 18.

Adding to 12312211221 its reverse (12211221321), we get a palindrome (24523432542).

The spelling of 12312211221 in words is "twelve billion, three hundred twelve million, two hundred eleven thousand, two hundred twenty-one".