18122238 has 64 divisors (see below), whose sum is σ = 44928000. Its totient is φ = 5380992.

The previous prime is 18122207. The next prime is 18122243. The reversal of 18122238 is 83222181.

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

It is a Curzon number.

It is a congruent number.

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, 16923 + ... + 17961.

It is an arithmetic number, because the mean of its divisors is an integer number (702000).

Almost surely, 2^18122238 is an apocalyptic number.

18122238 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 18122238, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22464000).

18122238 is an abundant number, since it is smaller than the sum of its proper divisors (26805762).

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

18122238 is a wasteful number, since it uses less digits than its factorization.

18122238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1086 (or 1080 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 18122238 is about 4257.0221986736. The cubic root of 18122238 is about 262.6660500414. Note that the first 3 decimals are identical.

The spelling of 18122238 in words is "eighteen million, one hundred twenty-two thousand, two hundred thirty-eight".