217172 has 6 divisors (see below), whose sum is σ = 380058. Its totient is φ = 108584.

The previous prime is 217169. The next prime is 217199. The reversal of 217172 is 271712.

It can be written as a sum of positive squares in only one way, i.e., 217156 + 16 = 466^2 + 4^2 .

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 27143 + ... + 27150.

It is an arithmetic number, because the mean of its divisors is an integer number (63343).

2²¹⁷¹⁷² is an apocalyptic number.

It is an amenable number.

217172 is a deficient number, since it is larger than the sum of its proper divisors (162886).

217172 is a wasteful number, since it uses less digits than its factorization.

217172 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54297 (or 54295 counting only the distinct ones).

The product of its digits is 196, while the sum is 20.

The square root of 217172 is about 466.0171670658. The cubic root of 217172 is about 60.1083228369.

Adding to 217172 its reverse (271712), we get a palindrome (488884).

It can be divided in two parts, 21717 and 2, that multiplied together give a palindrome (43434).

The spelling of 217172 in words is "two hundred seventeen thousand, one hundred seventy-two", and thus it is an iban number.