12181931 has 2 divisors, whose sum is σ = 12181932. Its totient is φ = 12181930.

The previous prime is 12181921. The next prime is 12181951. The reversal of 12181931 is 13918121.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12181931 - 2⁶ = 12181867 is a prime.

It is a super-2 number, since 2×12181931² = 296798885777522, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12181931.

It is not a weakly prime, because it can be changed into another prime (12181921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6090965 + 6090966.

It is an arithmetic number, because the mean of its divisors is an integer number (6090966).

Almost surely, 2^12181931 is an apocalyptic number.

12181931 is a deficient number, since it is larger than the sum of its proper divisors (1).

12181931 is an equidigital number, since it uses as much as digits as its factorization.

12181931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 432, while the sum is 26.

The square root of 12181931 is about 3490.2623110592. The cubic root of 12181931 is about 230.0940447166.

The spelling of 12181931 in words is "twelve million, one hundred eighty-one thousand, nine hundred thirty-one".