12736318781 has 2 divisors, whose sum is σ = 12736318782. Its totient is φ = 12736318780.

The previous prime is 12736318769. The next prime is 12736318787. The reversal of 12736318781 is 18781363721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10178993881 + 2557324900 = 100891^2 + 50570^2 .

It is an emirp because it is prime and its reverse (18781363721) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12736318781 is a prime.

It is a super-2 number, since 2×12736318781² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12736318787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6368159390 + 6368159391.

It is an arithmetic number, because the mean of its divisors is an integer number (6368159391).

Almost surely, 2^12736318781 is an apocalyptic number.

It is an amenable number.

12736318781 is a deficient number, since it is larger than the sum of its proper divisors (1).

12736318781 is an equidigital number, since it uses as much as digits as its factorization.

12736318781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 338688, while the sum is 47.

The spelling of 12736318781 in words is "twelve billion, seven hundred thirty-six million, three hundred eighteen thousand, seven hundred eighty-one".