871985 has 8 divisors (see below), whose sum is σ = 1061160. Its totient is φ = 687744.

The previous prime is 871973. The next prime is 871987. The reversal of 871985 is 589178.

871985 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 38416 + 833569 = 196^2 + 913^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 871985 - 2¹⁴ = 855601 is a prime.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 871985.

It is not an unprimeable number, because it can be changed into a prime (871987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 830 + ... + 1559.

It is an arithmetic number, because the mean of its divisors is an integer number (132645).

2⁸⁷¹⁹⁸⁵ is an apocalyptic number.

It is an amenable number.

871985 is a deficient number, since it is larger than the sum of its proper divisors (189175).

871985 is a wasteful number, since it uses less digits than its factorization.

871985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2467.

The product of its digits is 20160, while the sum is 38.

The square root of 871985 is about 933.8013707422. The cubic root of 871985 is about 95.5365758130.

The spelling of 871985 in words is "eight hundred seventy-one thousand, nine hundred eighty-five".