243813 has 8 divisors (see below), whose sum is σ = 330208. Its totient is φ = 159984.

The previous prime is 243809. The next prime is 243829. The reversal of 243813 is 318342.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 243813 - 2² = 243809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 243813.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 243813.

It is not an unprimeable number, because it can be changed into a prime (243863) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 406 + ... + 807.

It is an arithmetic number, because the mean of its divisors is an integer number (41276).

2²⁴³⁸¹³ is an apocalyptic number.

It is an amenable number.

243813 is a deficient number, since it is larger than the sum of its proper divisors (86395).

243813 is a wasteful number, since it uses less digits than its factorization.

243813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1283.

The product of its digits is 576, while the sum is 21.

The square root of 243813 is about 493.7742399113. The cubic root of 243813 is about 62.4720301515.

Subtracting 243813 from its reverse (318342), we obtain a square (74529 = 273²).

The spelling of 243813 in words is "two hundred forty-three thousand, eight hundred thirteen".