218045 has 4 divisors (see below), whose sum is σ = 261660. Its totient is φ = 174432.

The previous prime is 218021. The next prime is 218047. The reversal of 218045 is 540812.

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

It can be written as a sum of positive squares in 2 ways, for example, as 40804 + 177241 = 202^2 + 421^2 .

It is a cyclic number.

It is not a de Polignac number, because 218045 - 2⁶ = 217981 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218047) 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, 21800 + ... + 21809.

It is an arithmetic number, because the mean of its divisors is an integer number (65415).

2²¹⁸⁰⁴⁵ is an apocalyptic number.

It is an amenable number.

218045 is a deficient number, since it is larger than the sum of its proper divisors (43615).

218045 is an equidigital number, since it uses as much as digits as its factorization.

218045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43614.

The product of its (nonzero) digits is 320, while the sum is 20.

The square root of 218045 is about 466.9528884160. The cubic root of 218045 is about 60.1887574065.

Adding to 218045 its reverse (540812), we get a palindrome (758857).

The spelling of 218045 in words is "two hundred eighteen thousand, forty-five".