12638763757 has 4 divisors (see below), whose sum is σ = 12659793916. Its totient is φ = 12617733600.

The previous prime is 12638763743. The next prime is 12638763779. The reversal of 12638763757 is 75736783621.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 75736783621 = 4219 ⋅17951359.

It can be written as a sum of positive squares in 2 ways, for example, as 6539309956 + 6099453801 = 80866^2 + 78099^2 .

It is a cyclic number.

It is not a de Polignac number, because 12638763757 - 2²⁷ = 12504546029 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12638763698 and 12638763707.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12638763857) 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 in 3 ways as a sum of consecutive naturals, for example, 10514178 + ... + 10515379.

It is an arithmetic number, because the mean of its divisors is an integer number (3164948479).

Almost surely, 2^12638763757 is an apocalyptic number.

It is an amenable number.

12638763757 is a deficient number, since it is larger than the sum of its proper divisors (21030159).

12638763757 is an equidigital number, since it uses as much as digits as its factorization.

12638763757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21030158.

The product of its digits is 8890560, while the sum is 55.

The spelling of 12638763757 in words is "twelve billion, six hundred thirty-eight million, seven hundred sixty-three thousand, seven hundred fifty-seven".