217088 has 26 divisors (see below), whose sum is σ = 442314. Its totient is φ = 106496.

The previous prime is 217081. The next prime is 217111. The reversal of 217088 is 880712.

It can be written as a sum of positive squares in only one way, i.e., 200704 + 16384 = 448^2 + 128^2 .

It is a nialpdrome in base 4 and base 8.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217081) by changing a digit.

217088 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4070 + ... + 4122.

2²¹⁷⁰⁸⁸ 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 217088, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (221157).

217088 is an abundant number, since it is smaller than the sum of its proper divisors (225226).

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

217088 is an frugal number, since it uses more digits than its factorization.

217088 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77 (or 55 counting only the distinct ones).

The product of its (nonzero) digits is 896, while the sum is 26.

The square root of 217088 is about 465.9270329140. The cubic root of 217088 is about 60.1005720675.

The spelling of 217088 in words is "two hundred seventeen thousand, eighty-eight".