218243 has 4 divisors (see below), whose sum is σ = 223608. Its totient is φ = 212880.

The previous prime is 218233. The next prime is 218249. The reversal of 218243 is 342812.

218243 = T₈₂ + T₈₃ + ... + T₁₂₂.

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 218243 - 2⁴ = 218227 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 218243.

It is not an unprimeable number, because it can be changed into a prime (218249) 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, 2621 + ... + 2702.

It is an arithmetic number, because the mean of its divisors is an integer number (55902).

2²¹⁸²⁴³ is an apocalyptic number.

218243 is a deficient number, since it is larger than the sum of its proper divisors (5365).

218243 is an equidigital number, since it uses as much as digits as its factorization.

218243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5364.

The product of its digits is 384, while the sum is 20.

The square root of 218243 is about 467.1648531300. The cubic root of 218243 is about 60.2069704184.

The spelling of 218243 in words is "two hundred eighteen thousand, two hundred forty-three".