12781730671 has 2 divisors, whose sum is σ = 12781730672. Its totient is φ = 12781730670.

The previous prime is 12781730659. The next prime is 12781730713. The reversal of 12781730671 is 17603718721.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (17603718721) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12781730671 - 2¹⁷ = 12781599599 is a prime.

It is a super-2 number, since 2×12781730671² (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 (12781730641) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6390865335 + 6390865336.

It is an arithmetic number, because the mean of its divisors is an integer number (6390865336).

Almost surely, 2^12781730671 is an apocalyptic number.

12781730671 is a deficient number, since it is larger than the sum of its proper divisors (1).

12781730671 is an equidigital number, since it uses as much as digits as its factorization.

12781730671 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 98784, while the sum is 43.

The spelling of 12781730671 in words is "twelve billion, seven hundred eighty-one million, seven hundred thirty thousand, six hundred seventy-one".