172866 has 16 divisors (see below), whose sum is σ = 353664. Its totient is φ = 56304.

The previous prime is 172859. The next prime is 172867. The reversal of 172866 is 668271.

It is a happy number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (172867) by changing a digit.

172866 is an untouchable number, because it is not equal to the sum of proper divisors of any 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 in 7 ways as a sum of consecutive naturals, for example, 25 + ... + 588.

It is an arithmetic number, because the mean of its divisors is an integer number (22104).

2¹⁷²⁸⁶⁶ is an apocalyptic number.

172866 is an abundant number, since it is smaller than the sum of its proper divisors (180798).

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

172866 is a wasteful number, since it uses less digits than its factorization.

172866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 665.

The product of its digits is 4032, while the sum is 30.

The square root of 172866 is about 415.7715718998. The cubic root of 172866 is about 55.7061564170.

The spelling of 172866 in words is "one hundred seventy-two thousand, eight hundred sixty-six".