18216648 has 36 divisors (see below), whose sum is σ = 49435035. Its totient is φ = 6060144.

The previous prime is 18216641. The next prime is 18216661. The reversal of 18216648 is 84661281.

It is a powerful number, because all its prime factors have an exponent greater than 1 and also an Achilles number because it is not a perfect power.

18216648 is a `hidden beast` number, since 1 + 8 + 2 + 1 + 6 + 648 = 666.

It can be written as a sum of positive squares in only one way, i.e., 9108324 + 9108324 = 3018^2 + 3018^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=3018.

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

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (18216641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 35965 + ... + 36467.

Almost surely, 2^18216648 is an apocalyptic number.

18216648 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

18216648 is an abundant number, since it is smaller than the sum of its proper divisors (31218387).

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

18216648 is an equidigital number, since it uses as much as digits as its factorization.

18216648 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1018 (or 508 counting only the distinct ones).

The product of its digits is 18432, while the sum is 36.

The square root of 18216648 is about 4268.0965312420. The cubic root of 18216648 is about 263.1213904677.

Multiplying 18216648 by its product of digits (18432), we get a square (335769255936 = 579456²).

The spelling of 18216648 in words is "eighteen million, two hundred sixteen thousand, six hundred forty-eight".