18550 has 24 divisors (see below), whose sum is σ = 40176. Its totient is φ = 6240.

The previous prime is 18541. The next prime is 18553. The reversal of 18550 is 5581.

18550 is a Rhonda number in base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18553) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 324 + ... + 376.

It is an arithmetic number, because the mean of its divisors is an integer number (1674).

2¹⁸⁵⁵⁰ is an apocalyptic number.

18550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18550 is an abundant number, since it is smaller than the sum of its proper divisors (21626).

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 (20088).

18550 is a wasteful number, since it uses less digits than its factorization.

18550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72 (or 67 counting only the distinct ones).

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 18550 is about 136.1983847188. The cubic root of 18550 is about 26.4716678330.

The spelling of 18550 in words is "eighteen thousand, five hundred fifty".