217087 has 4 divisors (see below), whose sum is σ = 233800. Its totient is φ = 200376.

The previous prime is 217081. The next prime is 217111. The reversal of 217087 is 780712.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-217087 is a prime.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217081) 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, 8337 + ... + 8362.

It is an arithmetic number, because the mean of its divisors is an integer number (58450).

2²¹⁷⁰⁸⁷ is an apocalyptic number.

217087 is a deficient number, since it is larger than the sum of its proper divisors (16713).

217087 is a wasteful number, since it uses less digits than its factorization.

217087 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16712.

The product of its (nonzero) digits is 784, while the sum is 25.

The square root of 217087 is about 465.9259597833. The cubic root of 217087 is about 60.1004797844.

Adding to 217087 its reverse (780712), we get a palindrome (997799).

The spelling of 217087 in words is "two hundred seventeen thousand, eighty-seven".