18181800216 has 32 divisors (see below), whose sum is σ = 50505001200. Its totient is φ = 6060600000.

The previous prime is 18181800157. The next prime is 18181800229. The reversal of 18181800216 is 61200818181.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42087285 + ... + 42087716.

Almost surely, 2^18181800216 is an apocalyptic number.

It is an amenable number.

18181800216 is an abundant number, since it is smaller than the sum of its proper divisors (32323200984).

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

18181800216 is a wasteful number, since it uses less digits than its factorization.

18181800216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84175016 (or 84175006 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 36.

The spelling of 18181800216 in words is "eighteen billion, one hundred eighty-one million, eight hundred thousand, two hundred sixteen".