18858 has 16 divisors (see below), whose sum is σ = 43200. Its totient is φ = 5376.

The previous prime is 18839. The next prime is 18859. The reversal of 18858 is 85881.

18858 is nontrivially palindromic in base 13.

It is a Curzon number.

It is a plaindrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (18859) by changing a digit.

18858 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 183 + ... + 266.

It is an arithmetic number, because the mean of its divisors is an integer number (2700).

2¹⁸⁸⁵⁸ is an apocalyptic number.

18858 is an abundant number, since it is smaller than the sum of its proper divisors (24342).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21600).

18858 is a wasteful number, since it uses less digits than its factorization.

18858 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461.

The product of its digits is 2560, while the sum is 30.

The square root of 18858 is about 137.3244333686. The cubic root of 18858 is about 26.6173742185.

The spelling of 18858 in words is "eighteen thousand, eight hundred fifty-eight".