12312013221 has 24 divisors (see below), whose sum is σ = 17993082744. Its totient is φ = 8111817600.

The previous prime is 12312013211. The next prime is 12312013271. The reversal of 12312013221 is 12231021321.

It can be written as a sum of positive squares in 4 ways, for example, as 3218292900 + 9093720321 = 56730^2 + 95361^2 .

It is not a de Polignac number, because 12312013221 - 2¹⁵ = 12311980453 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12312013194 and 12312013203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12312013211) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 494155 + ... + 518471.

It is an arithmetic number, because the mean of its divisors is an integer number (749711781).

Almost surely, 2^12312013221 is an apocalyptic number.

It is an amenable number.

12312013221 is a deficient number, since it is larger than the sum of its proper divisors (5681069523).

12312013221 is a wasteful number, since it uses less digits than its factorization.

12312013221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24981 (or 24978 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 12312013221 its reverse (12231021321), we get a palindrome (24543034542).

The spelling of 12312013221 in words is "twelve billion, three hundred twelve million, thirteen thousand, two hundred twenty-one".