12681368261 has 2 divisors, whose sum is σ = 12681368262. Its totient is φ = 12681368260.

The previous prime is 12681368243. The next prime is 12681368267. The reversal of 12681368261 is 16286318621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7085430625 + 5595937636 = 84175^2 + 74806^2 .

It is an emirp because it is prime and its reverse (16286318621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12681368261 - 2¹⁸ = 12681106117 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12681368267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6340684130 + 6340684131.

It is an arithmetic number, because the mean of its divisors is an integer number (6340684131).

Almost surely, 2^12681368261 is an apocalyptic number.

It is an amenable number.

12681368261 is a deficient number, since it is larger than the sum of its proper divisors (1).

12681368261 is an equidigital number, since it uses as much as digits as its factorization.

12681368261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165888, while the sum is 44.

The spelling of 12681368261 in words is "twelve billion, six hundred eighty-one million, three hundred sixty-eight thousand, two hundred sixty-one".