173987 has 4 divisors (see below), whose sum is σ = 189816. Its totient is φ = 158160.

The previous prime is 173981. The next prime is 173993. The reversal of 173987 is 789371.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 789371 = 11 ⋅71761.

It is an interprime number because it is at equal distance from previous prime (173981) and next prime (173993).

It is a cyclic number.

It is not a de Polignac number, because 173987 - 2⁶ = 173923 is a prime.

It is a zygodrome in base 3.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 173987.

It is not an unprimeable number, because it can be changed into a prime (173981) 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, 7898 + ... + 7919.

It is an arithmetic number, because the mean of its divisors is an integer number (47454).

2¹⁷³⁹⁸⁷ is an apocalyptic number.

173987 is a deficient number, since it is larger than the sum of its proper divisors (15829).

173987 is a wasteful number, since it uses less digits than its factorization.

173987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15828.

The product of its digits is 10584, while the sum is 35.

The square root of 173987 is about 417.1174894439. The cubic root of 173987 is about 55.8263113369.

It can be divided in two parts, 17 and 3987, that added together give a palindrome (4004).

The spelling of 173987 in words is "one hundred seventy-three thousand, nine hundred eighty-seven".