12781931 has 2 divisors, whose sum is σ = 12781932. Its totient is φ = 12781930.

The previous prime is 12781919. The next prime is 12781939. The reversal of 12781931 is 13918721.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12781931 - 2¹⁰ = 12780907 is a prime.

It is a super-2 number, since 2×12781931² = 326755520177522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12781939) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6390965 + 6390966.

It is an arithmetic number, because the mean of its divisors is an integer number (6390966).

Almost surely, 2^12781931 is an apocalyptic number.

12781931 is a deficient number, since it is larger than the sum of its proper divisors (1).

12781931 is an equidigital number, since it uses as much as digits as its factorization.

12781931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3024, while the sum is 32.

The square root of 12781931 is about 3575.1826526766. The cubic root of 12781931 is about 233.8112962301.

The spelling of 12781931 in words is "twelve million, seven hundred eighty-one thousand, nine hundred thirty-one".