12638627557 has 2 divisors, whose sum is σ = 12638627558. Its totient is φ = 12638627556.

The previous prime is 12638627549. The next prime is 12638627567. The reversal of 12638627557 is 75572683621.

It is a happy number.

12638627557 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12630612996 + 8014561 = 112386^2 + 2831^2 .

It is a cyclic number.

It is not a de Polignac number, because 12638627557 - 2³ = 12638627549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12638627567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6319313778 + 6319313779.

It is an arithmetic number, because the mean of its divisors is an integer number (6319313779).

Almost surely, 2^12638627557 is an apocalyptic number.

It is an amenable number.

12638627557 is a deficient number, since it is larger than the sum of its proper divisors (1).

12638627557 is an equidigital number, since it uses as much as digits as its factorization.

12638627557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4233600, while the sum is 52.

The spelling of 12638627557 in words is "twelve billion, six hundred thirty-eight million, six hundred twenty-seven thousand, five hundred fifty-seven".