18855816 has 32 divisors (see below), whose sum is σ = 53874240. Its totient is φ = 5387328.

The previous prime is 18855797. The next prime is 18855821. The reversal of 18855816 is 61855881.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

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, 55951 + ... + 56286.

It is an arithmetic number, because the mean of its divisors is an integer number (1683570).

Almost surely, 2^18855816 is an apocalyptic number.

It is an amenable number.

18855816 is an abundant number, since it is smaller than the sum of its proper divisors (35018424).

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

18855816 is a wasteful number, since it uses less digits than its factorization.

18855816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 112253 (or 112249 counting only the distinct ones).

The product of its digits is 76800, while the sum is 42.

The square root of 18855816 is about 4342.3284076633. The cubic root of 18855816 is about 266.1634663354.

The spelling of 18855816 in words is "eighteen million, eight hundred fifty-five thousand, eight hundred sixteen".