218045317 has 4 divisors (see below), whose sum is σ = 249194656. Its totient is φ = 186895980.

The previous prime is 218045309. The next prime is 218045341. The reversal of 218045317 is 713540812.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 218045317 - 2³ = 218045309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218045357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15574659 + ... + 15574672.

It is an arithmetic number, because the mean of its divisors is an integer number (62298664).

Almost surely, 2^218045317 is an apocalyptic number.

It is an amenable number.

218045317 is a deficient number, since it is larger than the sum of its proper divisors (31149339).

218045317 is an equidigital number, since it uses as much as digits as its factorization.

218045317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31149338.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 218045317 is about 14766.3576077515. The cubic root of 218045317 is about 601.8878657452.

The spelling of 218045317 in words is "two hundred eighteen million, forty-five thousand, three hundred seventeen".