217385 has 8 divisors (see below), whose sum is σ = 298176. Its totient is φ = 149040.

The previous prime is 217369. The next prime is 217387. The reversal of 217385 is 583712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 217385 - 2⁴ = 217369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (217387) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3071 + ... + 3140.

It is an arithmetic number, because the mean of its divisors is an integer number (37272).

2²¹⁷³⁸⁵ is an apocalyptic number.

It is an amenable number.

217385 is a deficient number, since it is larger than the sum of its proper divisors (80791).

217385 is an equidigital number, since it uses as much as digits as its factorization.

217385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6223.

The product of its digits is 1680, while the sum is 26.

The square root of 217385 is about 466.2456434113. The cubic root of 217385 is about 60.1279676182.

The spelling of 217385 in words is "two hundred seventeen thousand, three hundred eighty-five".