243818 has 4 divisors (see below), whose sum is σ = 365730. Its totient is φ = 121908.

The previous prime is 243809. The next prime is 243829. The reversal of 243818 is 818342.

243818 = 137² + 138² + ... + 148².

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

It can be written as a sum of positive squares in only one way, i.e., 208849 + 34969 = 457^2 + 187^2 .

It is an Ulam number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 243818.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60953 + ... + 60956.

2²⁴³⁸¹⁸ is an apocalyptic number.

243818 is a deficient number, since it is larger than the sum of its proper divisors (121912).

243818 is a wasteful number, since it uses less digits than its factorization.

243818 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121911.

The product of its digits is 1536, while the sum is 26.

The square root of 243818 is about 493.7793029279. The cubic root of 243818 is about 62.4724571974.

It can be divided in two parts, 24381 and 8, that added together give a cube (24389 = 29³).

The spelling of 243818 in words is "two hundred forty-three thousand, eight hundred eighteen".