218340317 has 4 divisors (see below), whose sum is σ = 235135740. Its totient is φ = 201544896.

The previous prime is 218340301. The next prime is 218340319. The reversal of 218340317 is 713043812.

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 146192281 + 72148036 = 12091^2 + 8494^2 .

It is a cyclic number.

It is not a de Polignac number, because 218340317 - 2⁴ = 218340301 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 218340317.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218340319) 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, 8397692 + ... + 8397717.

It is an arithmetic number, because the mean of its divisors is an integer number (58783935).

Almost surely, 2^218340317 is an apocalyptic number.

It is an amenable number.

218340317 is a deficient number, since it is larger than the sum of its proper divisors (16795423).

218340317 is a wasteful number, since it uses less digits than its factorization.

218340317 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16795422.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 218340317 is about 14776.3431538388. The cubic root of 218340317 is about 602.1591807620.

The spelling of 218340317 in words is "two hundred eighteen million, three hundred forty thousand, three hundred seventeen".