12856813 has 2 divisors, whose sum is σ = 12856814. Its totient is φ = 12856812.

The previous prime is 12856759. The next prime is 12856849. The reversal of 12856813 is 31865821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9162729 + 3694084 = 3027^2 + 1922^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12856813 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12856873) 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, 6428406 + 6428407.

It is an arithmetic number, because the mean of its divisors is an integer number (6428407).

Almost surely, 2^12856813 is an apocalyptic number.

It is an amenable number.

12856813 is a deficient number, since it is larger than the sum of its proper divisors (1).

12856813 is an equidigital number, since it uses as much as digits as its factorization.

12856813 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 11520, while the sum is 34.

The square root of 12856813 is about 3585.6398313272. The cubic root of 12856813 is about 234.2669962348.

The spelling of 12856813 in words is "twelve million, eight hundred fifty-six thousand, eight hundred thirteen".