18123218 has 16 divisors (see below), whose sum is σ = 28460160. Its totient is φ = 8639136.

The previous prime is 18123211. The next prime is 18123223. The reversal of 18123218 is 81232181.

It is an alternating number because its digits alternate between odd and even.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18123211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21998 + ... + 22806.

It is an arithmetic number, because the mean of its divisors is an integer number (1778760).

Almost surely, 2^18123218 is an apocalyptic number.

18123218 is a deficient number, since it is larger than the sum of its proper divisors (10336942).

18123218 is a wasteful number, since it uses less digits than its factorization.

18123218 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1321.

The product of its digits is 768, while the sum is 26.

The square root of 18123218 is about 4257.1373010510. The cubic root of 18123218 is about 262.6707847047.

Adding to 18123218 its reverse (81232181), we get a palindrome (99355399).

The spelling of 18123218 in words is "eighteen million, one hundred twenty-three thousand, two hundred eighteen".