12312981 has 24 divisors (see below), whose sum is σ = 19656000. Its totient is φ = 7387776.

The previous prime is 12312973. The next prime is 12312991. The reversal of 12312981 is 18921321.

It is not a de Polignac number, because 12312981 - 2³ = 12312973 is a prime.

It is a super-2 number, since 2×12312981² = 303219002212722, which contains 22 as substring.

It is a Curzon number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12312901) 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, 1770 + ... + 5268.

It is an arithmetic number, because the mean of its divisors is an integer number (819000).

Almost surely, 2^12312981 is an apocalyptic number.

It is an amenable number.

12312981 is a deficient number, since it is larger than the sum of its proper divisors (7343019).

12312981 is a wasteful number, since it uses less digits than its factorization.

12312981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3545 (or 3542 counting only the distinct ones).

The product of its digits is 864, while the sum is 27.

The square root of 12312981 is about 3508.9857508973. The cubic root of 12312981 is about 230.9162005591.

The spelling of 12312981 in words is "twelve million, three hundred twelve thousand, nine hundred eighty-one".