12815865108 has 72 divisors (see below), whose sum is σ = 32888856000. Its totient is φ = 4207095936.

The previous prime is 12815865077. The next prime is 12815865109. The reversal of 12815865108 is 80156851821.

12815865108 is a `hidden beast` number, since 1 + 2 + 81 + 58 + 6 + 510 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12815865109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1938793 + ... + 1945391.

Almost surely, 2^12815865108 is an apocalyptic number.

12815865108 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 12815865108, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16444428000).

12815865108 is an abundant number, since it is smaller than the sum of its proper divisors (20072990892).

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

12815865108 is a wasteful number, since it uses less digits than its factorization.

12815865108 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7421 (or 7416 counting only the distinct ones).

The product of its (nonzero) digits is 153600, while the sum is 45.

The spelling of 12815865108 in words is "twelve billion, eight hundred fifteen million, eight hundred sixty-five thousand, one hundred eight".