13581215568 has 240 divisors, whose sum is σ = 40934380032. Its totient is φ = 4354560000.

The previous prime is 13581215521. The next prime is 13581215587. The reversal of 13581215568 is 86551218531.

13581215568 is a `hidden beast` number, since 1 + 3 + 5 + 81 + 2 + 1 + 5 + 568 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 33868168 + ... + 33868568.

Almost surely, 2^13581215568 is an apocalyptic number.

13581215568 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 13581215568, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20467190016).

13581215568 is an abundant number, since it is smaller than the sum of its proper divisors (27353164464).

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

13581215568 is a wasteful number, since it uses less digits than its factorization.

13581215568 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 736 (or 718 counting only the distinct ones).

The product of its digits is 288000, while the sum is 45.

The spelling of 13581215568 in words is "thirteen billion, five hundred eighty-one million, two hundred fifteen thousand, five hundred sixty-eight".