243823 has 4 divisors (see below), whose sum is σ = 254448. Its totient is φ = 233200.

The previous prime is 243809. The next prime is 243829. The reversal of 243823 is 328342.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 243823 - 2⁹ = 243311 is a prime.

It is a Duffinian number.

243823 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 243794 and 243803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243829) 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, 5278 + ... + 5323.

It is an arithmetic number, because the mean of its divisors is an integer number (63612).

2²⁴³⁸²³ is an apocalyptic number.

243823 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

243823 is a deficient number, since it is larger than the sum of its proper divisors (10625).

243823 is a wasteful number, since it uses less digits than its factorization.

243823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10624.

The product of its digits is 1152, while the sum is 22.

The square root of 243823 is about 493.7843658926. The cubic root of 243823 is about 62.4728842375.

The spelling of 243823 in words is "two hundred forty-three thousand, eight hundred twenty-three".