18412218 has 64 divisors (see below), whose sum is σ = 45158400. Its totient is φ = 5514480.

The previous prime is 18412201. The next prime is 18412237. The reversal of 18412218 is 81221481.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 18412191 and 18412200.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 82455 + ... + 82677.

It is an arithmetic number, because the mean of its divisors is an integer number (705600).

Almost surely, 2^18412218 is an apocalyptic number.

18412218 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 18412218, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22579200).

18412218 is an abundant number, since it is smaller than the sum of its proper divisors (26746182).

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

18412218 is a wasteful number, since it uses less digits than its factorization.

18412218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384 (or 378 counting only the distinct ones).

The product of its digits is 1024, while the sum is 27.

The square root of 18412218 is about 4290.9460495327. The cubic root of 18412218 is about 264.0596456141.

Adding to 18412218 its reverse (81221481), we get a palindrome (99633699).

The spelling of 18412218 in words is "eighteen million, four hundred twelve thousand, two hundred eighteen".