18087816 has 16 divisors (see below), whose sum is σ = 45219600. Its totient is φ = 6029264.

The previous prime is 18087757. The next prime is 18087827. The reversal of 18087816 is 61878081.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 376806 + ... + 376853.

It is an arithmetic number, because the mean of its divisors is an integer number (2826225).

Almost surely, 2^18087816 is an apocalyptic number.

It is an amenable number.

18087816 is an abundant number, since it is smaller than the sum of its proper divisors (27131784).

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

18087816 is a wasteful number, since it uses less digits than its factorization.

18087816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 753668 (or 753664 counting only the distinct ones).

The product of its (nonzero) digits is 21504, while the sum is 39.

The square root of 18087816 is about 4252.9773100735. The cubic root of 18087816 is about 262.4996390018.

The spelling of 18087816 in words is "eighteen million, eighty-seven thousand, eight hundred sixteen".