12816812461 has 2 divisors, whose sum is σ = 12816812462. Its totient is φ = 12816812460.

The previous prime is 12816812423. The next prime is 12816812471. The reversal of 12816812461 is 16421861821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11708322025 + 1108490436 = 108205^2 + 33294^2 .

It is a cyclic number.

It is not a de Polignac number, because 12816812461 - 2²⁷ = 12682594733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12816812471) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6408406230 + 6408406231.

It is an arithmetic number, because the mean of its divisors is an integer number (6408406231).

Almost surely, 2^12816812461 is an apocalyptic number.

It is an amenable number.

12816812461 is a deficient number, since it is larger than the sum of its proper divisors (1).

12816812461 is an equidigital number, since it uses as much as digits as its factorization.

12816812461 is an evil number, because the sum of its binary digits is even.

The product of its digits is 36864, while the sum is 40.

The spelling of 12816812461 in words is "twelve billion, eight hundred sixteen million, eight hundred twelve thousand, four hundred sixty-one".