12818685438 has 24 divisors (see below), whose sum is σ = 29910266568. Its totient is φ = 3944210832.

The previous prime is 12818685433. The next prime is 12818685443. The reversal of 12818685438 is 83458681821.

12818685438 is a `hidden beast` number, since 1 + 28 + 18 + 68 + 543 + 8 = 666.

It is an interprime number because it is at equal distance from previous prime (12818685433) and next prime (12818685443).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12818685433) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 27390120 + ... + 27390587.

It is an arithmetic number, because the mean of its divisors is an integer number (1246261107).

Almost surely, 2^12818685438 is an apocalyptic number.

12818685438 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12818685438 is an abundant number, since it is smaller than the sum of its proper divisors (17091581130).

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

12818685438 is a wasteful number, since it uses less digits than its factorization.

12818685438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54780728 (or 54780725 counting only the distinct ones).

The product of its digits is 2949120, while the sum is 54.

The spelling of 12818685438 in words is "twelve billion, eight hundred eighteen million, six hundred eighty-five thousand, four hundred thirty-eight".