171982 has 4 divisors (see below), whose sum is σ = 257976. Its totient is φ = 85990.

The previous prime is 171947. The next prime is 172001. The reversal of 171982 is 289171.

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

It is a self number, because there is not a number n which added to its sum of digits gives 171982.

It is a congruent number.

It is an unprimeable number.

171982 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42994 + ... + 42997.

It is an arithmetic number, because the mean of its divisors is an integer number (64494).

2¹⁷¹⁹⁸² is an apocalyptic number.

171982 is a deficient number, since it is larger than the sum of its proper divisors (85994).

171982 is an equidigital number, since it uses as much as digits as its factorization.

171982 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85993.

The product of its digits is 1008, while the sum is 28.

The square root of 171982 is about 414.7071255718. The cubic root of 171982 is about 55.6110376099.

The spelling of 171982 in words is "one hundred seventy-one thousand, nine hundred eighty-two".