18724 has 12 divisors (see below), whose sum is σ = 34048. Its totient is φ = 9000.

The previous prime is 18719. The next prime is 18731. The reversal of 18724 is 42781.

18724 is nontrivially palindromic in base 8.

18724 is a nontrivial repdigit in base 8.

It is a plaindrome in base 8.

It is a nialpdrome in base 8.

It is a zygodrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 18695 and 18704.

It is a congruent number.

It is an unprimeable number.

18724 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 (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 49 + ... + 199.

2¹⁸⁷²⁴ is an apocalyptic number.

It is an amenable number.

18724 is a deficient number, since it is larger than the sum of its proper divisors (15324).

18724 is a wasteful number, since it uses less digits than its factorization.

18724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 186 (or 184 counting only the distinct ones).

The product of its digits is 448, while the sum is 22.

The square root of 18724 is about 136.8356678648. The cubic root of 18724 is about 26.5541789391.

The spelling of 18724 in words is "eighteen thousand, seven hundred twenty-four".