166217 has 4 divisors (see below), whose sum is σ = 167040. Its totient is φ = 165396.

The previous prime is 166207. The next prime is 166219. The reversal of 166217 is 712661.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 166217 - 2⁸ = 165961 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 166192 and 166201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (166219) 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 3 ways as a sum of consecutive naturals, for example, 128 + ... + 590.

It is an arithmetic number, because the mean of its divisors is an integer number (41760).

2¹⁶⁶²¹⁷ is an apocalyptic number.

It is an amenable number.

166217 is a deficient number, since it is larger than the sum of its proper divisors (823).

166217 is an equidigital number, since it uses as much as digits as its factorization.

166217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822.

The product of its digits is 504, while the sum is 23.

The square root of 166217 is about 407.6971915528. The cubic root of 166217 is about 54.9825840174.

Adding to 166217 its reverse (712661), we get a palindrome (878878).

It can be divided in two parts, 166 and 217, that added together give a palindrome (383).

The spelling of 166217 in words is "one hundred sixty-six thousand, two hundred seventeen".