18718013556 has 144 divisors (see below), whose sum is σ = 52997870016. Its totient is φ = 5520960000.

The previous prime is 18718013543. The next prime is 18718013593. The reversal of 18718013556 is 65531081781.

18718013556 is a `hidden beast` number, since 1 + 8 + 7 + 1 + 80 + 13 + 556 = 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, 8782611 + ... + 8784741.

It is an arithmetic number, because the mean of its divisors is an integer number (368040764).

Almost surely, 2^18718013556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18718013556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26498935008).

18718013556 is an abundant number, since it is smaller than the sum of its proper divisors (34279856460).

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

18718013556 is a wasteful number, since it uses less digits than its factorization.

18718013556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2734 (or 2729 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 45.

The spelling of 18718013556 in words is "eighteen billion, seven hundred eighteen million, thirteen thousand, five hundred fifty-six".