12766991 has 2 divisors, whose sum is σ = 12766992. Its totient is φ = 12766990.

The previous prime is 12766987. The next prime is 12767003. The reversal of 12766991 is 19966721.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 12766991 - 2² = 12766987 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12766921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6383495 + 6383496.

It is an arithmetic number, because the mean of its divisors is an integer number (6383496).

Almost surely, 2^12766991 is an apocalyptic number.

12766991 is a deficient number, since it is larger than the sum of its proper divisors (1).

12766991 is an equidigital number, since it uses as much as digits as its factorization.

12766991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40824, while the sum is 41.

The square root of 12766991 is about 3573.0926380378. The cubic root of 12766991 is about 233.7201649130.

The spelling of 12766991 in words is "twelve million, seven hundred sixty-six thousand, nine hundred ninety-one".