12686621538 has 16 divisors (see below), whose sum is σ = 25374370176. Its totient is φ = 4228686000.

The previous prime is 12686621489. The next prime is 12686621579. The reversal of 12686621538 is 83512668621.

It is a happy number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 196288 + ... + 252788.

It is an arithmetic number, because the mean of its divisors is an integer number (1585898136).

Almost surely, 2^12686621538 is an apocalyptic number.

12686621538 is an abundant number, since it is smaller than the sum of its proper divisors (12687748638).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

12686621538 is a wasteful number, since it uses less digits than its factorization.

12686621538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93929.

The product of its digits is 829440, while the sum is 48.

The spelling of 12686621538 in words is "twelve billion, six hundred eighty-six million, six hundred twenty-one thousand, five hundred thirty-eight".