12663686338 has 4 divisors (see below), whose sum is σ = 18995529510. Its totient is φ = 6331843168.

The previous prime is 12663686317. The next prime is 12663686339. The reversal of 12663686338 is 83368636621.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 8202381489 + 4461304849 = 90567^2 + 66793^2 .

It is not an unprimeable number, because it can be changed into a prime (12663686339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3165921583 + ... + 3165921586.

Almost surely, 2^12663686338 is an apocalyptic number.

12663686338 is a deficient number, since it is larger than the sum of its proper divisors (6331843172).

12663686338 is an equidigital number, since it uses as much as digits as its factorization.

12663686338 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6331843171.

The product of its digits is 4478976, while the sum is 52.

The spelling of 12663686338 in words is "twelve billion, six hundred sixty-three million, six hundred eighty-six thousand, three hundred thirty-eight".