170987 has 4 divisors (see below), whose sum is σ = 172200. Its totient is φ = 169776.

The previous prime is 170971. The next prime is 171007. The reversal of 170987 is 789071.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789071 = 641 ⋅1231.

It is a cyclic number.

It is not a de Polignac number, because 170987 - 2⁴ = 170971 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 170987.

It is not an unprimeable number, because it can be changed into a prime (170927) 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, 362 + ... + 687.

It is an arithmetic number, because the mean of its divisors is an integer number (43050).

2¹⁷⁰⁹⁸⁷ is an apocalyptic number.

170987 is a deficient number, since it is larger than the sum of its proper divisors (1213).

170987 is a wasteful number, since it uses less digits than its factorization.

170987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1212.

The product of its (nonzero) digits is 3528, while the sum is 32.

The square root of 170987 is about 413.5057436119. The cubic root of 170987 is about 55.5035844342.

The spelling of 170987 in words is "one hundred seventy thousand, nine hundred eighty-seven".