18530 has 16 divisors (see below), whose sum is σ = 35640. Its totient is φ = 6912.

The previous prime is 18523. The next prime is 18539. The reversal of 18530 is 3581.

It can be written as a sum of positive squares in 4 ways, for example, as 17689 + 841 = 133^2 + 29^2 .

It is a Harshad number since it is a multiple of its sum of digits (17).

18530 is an undulating number in base 13.

It is a Curzon number.

It is a nialpdrome in base 12.

It is a junction number, because it is equal to n+sod(n) for n = 18499 and 18508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18539) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116 + ... + 224.

2¹⁸⁵³⁰ is an apocalyptic number.

18530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

18530 is a deficient number, since it is larger than the sum of its proper divisors (17110).

18530 is a wasteful number, since it uses less digits than its factorization.

18530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 18530 is about 136.1249426079. The cubic root of 18530 is about 26.4621507846.

The spelling of 18530 in words is "eighteen thousand, five hundred thirty".