12781703827217 has 12 divisors (see below), whose sum is σ = 13841188240860. Its totient is φ = 11797945967808.

The previous prime is 12781703827181. The next prime is 12781703827219. The reversal of 12781703827217 is 71272830718721.

It can be written as a sum of positive squares in 6 ways, for example, as 5831568138496 + 6950135688721 = 2414864^2 + 2636311^2 .

It is not a de Polignac number, because 12781703827217 - 2⁴⁰ = 11682192199441 is a prime.

It is a Smith number, since the sum of its digits (56) coincides with the sum of the digits of its prime factors.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12781703827219) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1896923 + ... + 5400159.

It is an arithmetic number, because the mean of its divisors is an integer number (1153432353405).

Almost surely, 2^{12781703827217} is an apocalyptic number.

It is an amenable number.

12781703827217 is a deficient number, since it is larger than the sum of its proper divisors (1059484413643).

12781703827217 is a wasteful number, since it uses less digits than its factorization.

12781703827217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3524852 (or 3524839 counting only the distinct ones).

The product of its (nonzero) digits is 3687936, while the sum is 56.

The spelling of 12781703827217 in words is "twelve trillion, seven hundred eighty-one billion, seven hundred three million, eight hundred twenty-seven thousand, two hundred seventeen".