18190218 has 16 divisors (see below), whose sum is σ = 36626400. Its totient is φ = 6022416.

The previous prime is 18190127. The next prime is 18190223. The reversal of 18190218 is 81209181.

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, 9280 + ... + 11067.

It is an arithmetic number, because the mean of its divisors is an integer number (2289150).

Almost surely, 2^18190218 is an apocalyptic number.

18190218 is an abundant number, since it is smaller than the sum of its proper divisors (18436182).

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

18190218 is a wasteful number, since it uses less digits than its factorization.

18190218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20501.

The product of its (nonzero) digits is 1152, while the sum is 30.

The square root of 18190218 is about 4264.9991793669. Note that the first 3 decimals coincide. The cubic root of 18190218 is about 262.9940771749.

Adding to 18190218 its reverse (81209181), we get a palindrome (99399399).

The spelling of 18190218 in words is "eighteen million, one hundred ninety thousand, two hundred eighteen".