12778937813 has 2 divisors, whose sum is σ = 12778937814. Its totient is φ = 12778937812.

The previous prime is 12778937779. The next prime is 12778937827. The reversal of 12778937813 is 31873987721.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8870437489 + 3908500324 = 94183^2 + 62518^2 .

It is a cyclic number.

It is not a de Polignac number, because 12778937813 - 2⁸ = 12778937557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12778937833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6389468906 + 6389468907.

It is an arithmetic number, because the mean of its divisors is an integer number (6389468907).

Almost surely, 2^12778937813 is an apocalyptic number.

It is an amenable number.

12778937813 is a deficient number, since it is larger than the sum of its proper divisors (1).

12778937813 is an equidigital number, since it uses as much as digits as its factorization.

12778937813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3556224, while the sum is 56.

The spelling of 12778937813 in words is "twelve billion, seven hundred seventy-eight million, nine hundred thirty-seven thousand, eight hundred thirteen".