171856 has 20 divisors (see below), whose sum is σ = 348192. Its totient is φ = 82016.

The previous prime is 171851. The next prime is 171863. The reversal of 171856 is 658171.

It is a happy number.

171856 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

Together with 176336 it forms an amicable pair .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (171851) 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, 135 + ... + 601.

2¹⁷¹⁸⁵⁶ is an apocalyptic number.

171856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 171856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (174096).

171856 is an abundant number, since it is smaller than the sum of its proper divisors (176336).

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

171856 is a wasteful number, since it uses less digits than its factorization.

171856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498 (or 492 counting only the distinct ones).

The product of its digits is 1680, while the sum is 28.

The square root of 171856 is about 414.5551832989. Note that the first 3 decimals coincide. The cubic root of 171856 is about 55.5974534313.

The spelling of 171856 in words is "one hundred seventy-one thousand, eight hundred fifty-six".