243923 has 4 divisors (see below), whose sum is σ = 244968. Its totient is φ = 242880.

The previous prime is 243917. The next prime is 243931. The reversal of 243923 is 329342.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243923 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8 + ... + 698.

It is an arithmetic number, because the mean of its divisors is an integer number (61242).

2²⁴³⁹²³ is an apocalyptic number.

243923 is a deficient number, since it is larger than the sum of its proper divisors (1045).

243923 is an equidigital number, since it uses as much as digits as its factorization.

243923 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1044.

The product of its digits is 1296, while the sum is 23.

The square root of 243923 is about 493.8856142874. The cubic root of 243923 is about 62.4814238127.

The spelling of 243923 in words is "two hundred forty-three thousand, nine hundred twenty-three".