18219208 has 16 divisors (see below), whose sum is σ = 39041280. Its totient is φ = 7808208.

The previous prime is 18219203. The next prime is 18219251. The reversal of 18219208 is 80291281.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 18219208.

It is not an unprimeable number, because it can be changed into a prime (18219203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 162616 + ... + 162727.

It is an arithmetic number, because the mean of its divisors is an integer number (2440080).

Almost surely, 2^18219208 is an apocalyptic number.

It is an amenable number.

18219208 is an abundant number, since it is smaller than the sum of its proper divisors (20822072).

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

18219208 is a wasteful number, since it uses less digits than its factorization.

18219208 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 325356 (or 325352 counting only the distinct ones).

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 18219208 is about 4268.3964202028. The cubic root of 18219208 is about 263.1337154430.

The spelling of 18219208 in words is "eighteen million, two hundred nineteen thousand, two hundred eight".