217116 has 36 divisors (see below), whose sum is σ = 567112. Its totient is φ = 69984.

The previous prime is 217111. The next prime is 217117. The reversal of 217116 is 611712.

Added to its reverse (611712) it gives a triangular number (828828 = T₁₂₈₇).

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1251 + ... + 1413.

2²¹⁷¹¹⁶ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 217116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (283556).

217116 is an abundant number, since it is smaller than the sum of its proper divisors (349996).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

217116 is a wasteful number, since it uses less digits than its factorization.

217116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210 (or 205 counting only the distinct ones).

The product of its digits is 84, while the sum is 18.

The square root of 217116 is about 465.9570795685. The cubic root of 217116 is about 60.1031558794.

Adding to 217116 its reverse (611712), we get a palindrome (828828).

It can be divided in two parts, 2171 and 16, that added together give a 7-th power (2187 = 3⁷).

The spelling of 217116 in words is "two hundred seventeen thousand, one hundred sixteen".