12806861 has 2 divisors, whose sum is σ = 12806862. Its totient is φ = 12806860.

The previous prime is 12806749. The next prime is 12806863. The reversal of 12806861 is 16860821.

12806861 = 2530² + 2531².

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6405961 + 6400900 = 2531^2 + 2530^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12806861 is a prime.

Together with 12806863, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12806863) 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, 6403430 + 6403431.

It is an arithmetic number, because the mean of its divisors is an integer number (6403431).

Almost surely, 2^12806861 is an apocalyptic number.

12806861 is the 2531-st centered square number.

It is an amenable number.

12806861 is a deficient number, since it is larger than the sum of its proper divisors (1).

12806861 is an equidigital number, since it uses as much as digits as its factorization.

12806861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4608, while the sum is 32.

The square root of 12806861 is about 3578.6674894435. The cubic root of 12806861 is about 233.9632067702.

The spelling of 12806861 in words is "twelve million, eight hundred six thousand, eight hundred sixty-one".