18660 has 24 divisors (see below), whose sum is σ = 52416. Its totient is φ = 4960.

The previous prime is 18637. The next prime is 18661. The reversal of 18660 is 6681.

18660 is nontrivially palindromic in base 8.

It is a nialpdrome in base 6, base 12 and base 13.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 18660.

It is not an unprimeable number, because it can be changed into a prime (18661) by changing a digit.

18660 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96 + ... + 215.

It is an arithmetic number, because the mean of its divisors is an integer number (2184).

2¹⁸⁶⁶⁰ is an apocalyptic number.

18660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18660 is an abundant number, since it is smaller than the sum of its proper divisors (33756).

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 (26208).

18660 is a wasteful number, since it uses less digits than its factorization.

18660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 323 (or 321 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 18660 is about 136.6016105322. The cubic root of 18660 is about 26.5238896947.

Adding to 18660 its sum of digits (21), we get a palindrome (18681).

The spelling of 18660 in words is "eighteen thousand, six hundred sixty".