18006816 has 48 divisors (see below), whose sum is σ = 47736864. Its totient is φ = 5942784.

The previous prime is 18006763. The next prime is 18006839. The reversal of 18006816 is 61860081.

It is a tau number, because it is divible by the number of its divisors (48).

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, 9396 + ... + 11148.

It is an arithmetic number, because the mean of its divisors is an integer number (994518).

Almost surely, 2^18006816 is an apocalyptic number.

18006816 is a gapful number since it is divisible by the number (16) 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 18006816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23868432).

18006816 is an abundant number, since it is smaller than the sum of its proper divisors (29730048).

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

18006816 is a wasteful number, since it uses less digits than its factorization.

18006816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1873 (or 1865 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 30.

The square root of 18006816 is about 4243.4438843939. The cubic root of 18006816 is about 262.1072148267.

Adding to 18006816 its reverse (61860081), we get a palindrome (79866897).

The spelling of 18006816 in words is "eighteen million, six thousand, eight hundred sixteen".