18667 has 4 divisors (see below), whose sum is σ = 20376. Its totient is φ = 16960.

The previous prime is 18661. The next prime is 18671. The reversal of 18667 is 76681.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 76681 = 11 ⋅6971.

It is a cyclic number.

It is not a de Polignac number, because 18667 - 2⁷ = 18539 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a nialpdrome in base 12.

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

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 838 + ... + 859.

It is an arithmetic number, because the mean of its divisors is an integer number (5094).

2¹⁸⁶⁶⁷ is an apocalyptic number.

18667 is a deficient number, since it is larger than the sum of its proper divisors (1709).

18667 is a wasteful number, since it uses less digits than its factorization.

18667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1708.

The product of its digits is 2016, while the sum is 28.

The square root of 18667 is about 136.6272300824. The cubic root of 18667 is about 26.5272059508.

It can be divided in two parts, 186 and 67, that added together give a triangular number (253 = T₂₂).

The spelling of 18667 in words is "eighteen thousand, six hundred sixty-seven".