18338238 has 48 divisors (see below), whose sum is σ = 41736240. Its totient is φ = 6034176.

The previous prime is 18338233. The next prime is 18338239. The reversal of 18338238 is 83283381.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18338233) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46948 + ... + 47336.

It is an arithmetic number, because the mean of its divisors is an integer number (869505).

Almost surely, 2^18338238 is an apocalyptic number.

18338238 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 18338238, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20868120).

18338238 is an abundant number, since it is smaller than the sum of its proper divisors (23398002).

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

18338238 is an equidigital number, since it uses as much as digits as its factorization.

18338238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 503 (or 491 counting only the distinct ones).

The product of its digits is 27648, while the sum is 36.

The square root of 18338238 is about 4282.3168962607. The cubic root of 18338238 is about 263.7055083941.

The spelling of 18338238 in words is "eighteen million, three hundred thirty-eight thousand, two hundred thirty-eight".