12778557137 has 2 divisors, whose sum is σ = 12778557138. Its totient is φ = 12778557136.

The previous prime is 12778557109. The next prime is 12778557271. The reversal of 12778557137 is 73175587721.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12581884561 + 196672576 = 112169^2 + 14024^2 .

It is a cyclic number.

It is not a de Polignac number, because 12778557137 - 2¹⁰ = 12778556113 is a prime.

It is not a weakly prime, because it can be changed into another prime (12778550137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6389278568 + 6389278569.

It is an arithmetic number, because the mean of its divisors is an integer number (6389278569).

Almost surely, 2^12778557137 is an apocalyptic number.

It is an amenable number.

12778557137 is a deficient number, since it is larger than the sum of its proper divisors (1).

12778557137 is an equidigital number, since it uses as much as digits as its factorization.

12778557137 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2881200, while the sum is 53.

The spelling of 12778557137 in words is "twelve billion, seven hundred seventy-eight million, five hundred fifty-seven thousand, one hundred thirty-seven".