12638777512639 has 4 divisors (see below), whose sum is σ = 12643720330024. Its totient is φ = 12633834695256.

The previous prime is 12638777512511. The next prime is 12638777512661. The reversal of 12638777512639 is 93621577783621.

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

It is a cyclic number.

It is not a de Polignac number, because 12638777512639 - 2⁷ = 12638777512511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12638777516639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2471404857 + ... + 2471409970.

It is an arithmetic number, because the mean of its divisors is an integer number (3160930082506).

Almost surely, 2^{12638777512639} is an apocalyptic number.

12638777512639 is a deficient number, since it is larger than the sum of its proper divisors (4942817385).

12638777512639 is an equidigital number, since it uses as much as digits as its factorization.

12638777512639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4942817384.

The product of its digits is 160030080, while the sum is 67.

The spelling of 12638777512639 in words is "twelve trillion, six hundred thirty-eight billion, seven hundred seventy-seven million, five hundred twelve thousand, six hundred thirty-nine".