18500238 has 20 divisors (see below), whose sum is σ = 41454600. Its totient is φ = 6166692.

The previous prime is 18500227. The next prime is 18500239. The reversal of 18500238 is 83200581.

It is a happy number.

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 not an unprimeable number, because it can be changed into a prime (18500239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 56938 + ... + 57261.

It is an arithmetic number, because the mean of its divisors is an integer number (2072730).

Almost surely, 2^18500238 is an apocalyptic number.

18500238 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

18500238 is an abundant number, since it is smaller than the sum of its proper divisors (22954362).

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

18500238 is a wasteful number, since it uses less digits than its factorization.

18500238 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114213 (or 114204 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 18500238 is about 4301.1903003704. The cubic root of 18500238 is about 264.4797577904.

The spelling of 18500238 in words is "eighteen million, five hundred thousand, two hundred thirty-eight".