18723 has 6 divisors (see below), whose sum is σ = 25284. Its totient is φ = 12324.

The previous prime is 18719. The next prime is 18731. The reversal of 18723 is 32781.

18723 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 18723 - 2² = 18719 is a prime.

It is an alternating number because its digits alternate between odd and even.

18723 is a lucky number.

It is a nialpdrome in base 8.

It is a self number, because there is not a number n which added to its sum of digits gives 18723.

It is not an unprimeable number, because it can be changed into a prime (18713) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 198 + ... + 276.

It is an arithmetic number, because the mean of its divisors is an integer number (4214).

18723 is a Friedman number, since it can be written as 3*(78+1)^2, using all its digits and the basic arithmetic operations.

2¹⁸⁷²³ is an apocalyptic number.

18723 is a deficient number, since it is larger than the sum of its proper divisors (6561).

18723 is an frugal number, since it uses more digits than its factorization.

18723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161 (or 82 counting only the distinct ones).

The product of its digits is 336, while the sum is 21.

The square root of 18723 is about 136.8320137979. The cubic root of 18723 is about 26.5537062009.

It can be divided in two parts, 187 and 23, that added together give a triangular number (210 = T₂₀).

The spelling of 18723 in words is "eighteen thousand, seven hundred twenty-three".