218245 has 4 divisors (see below), whose sum is σ = 261900. Its totient is φ = 174592.

The previous prime is 218233. The next prime is 218249. The reversal of 218245 is 542812.

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 93636 + 124609 = 306^2 + 353^2 .

It is a cyclic number.

It is not a de Polignac number, because 218245 - 2⁵ = 218213 is a prime.

218245 is a lucky number.

It is a congruent number.

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, 21820 + ... + 21829.

It is an arithmetic number, because the mean of its divisors is an integer number (65475).

2²¹⁸²⁴⁵ is an apocalyptic number.

It is an amenable number.

218245 is a deficient number, since it is larger than the sum of its proper divisors (43655).

218245 is an equidigital number, since it uses as much as digits as its factorization.

218245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43654.

The product of its digits is 640, while the sum is 22.

The square root of 218245 is about 467.1669936971. The cubic root of 218245 is about 60.2071543320.

The spelling of 218245 in words is "two hundred eighteen thousand, two hundred forty-five".