171988 has 24 divisors (see below), whose sum is σ = 331520. Its totient is φ = 77760.

The previous prime is 171947. The next prime is 172001. The reversal of 171988 is 889171.

It is a congruent number.

It is an unprimeable number.

171988 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 (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2320 + ... + 2392.

2¹⁷¹⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

171988 is a deficient number, since it is larger than the sum of its proper divisors (159532).

171988 is a wasteful number, since it uses less digits than its factorization.

171988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127 (or 125 counting only the distinct ones).

The product of its digits is 4032, while the sum is 34.

The square root of 171988 is about 414.7143595295. The cubic root of 171988 is about 55.6116843101.

The spelling of 171988 in words is "one hundred seventy-one thousand, nine hundred eighty-eight".