217055 has 4 divisors (see below), whose sum is σ = 260472. Its totient is φ = 173640.

The previous prime is 217033. The next prime is 217057. The reversal of 217055 is 550712.

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

It is not a de Polignac number, because 217055 - 2⁶ = 216991 is a prime.

It is a super-2 number, since 2×217055² = 94225746050, which contains 22 as substring.

It is an Ulam number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217057) 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, 21701 + ... + 21710.

It is an arithmetic number, because the mean of its divisors is an integer number (65118).

2²¹⁷⁰⁵⁵ is an apocalyptic number.

217055 is a deficient number, since it is larger than the sum of its proper divisors (43417).

217055 is an equidigital number, since it uses as much as digits as its factorization.

217055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43416.

The product of its (nonzero) digits is 350, while the sum is 20.

The square root of 217055 is about 465.8916182976. The cubic root of 217055 is about 60.0975265754.

Adding to 217055 its reverse (550712), we get a palindrome (767767).

The spelling of 217055 in words is "two hundred seventeen thousand, fifty-five".