871812 has 36 divisors (see below), whose sum is σ = 2245516. Its totient is φ = 285120.

The previous prime is 871789. The next prime is 871817. The reversal of 871812 is 218178.

It can be written as a sum of positive squares in 2 ways, for example, as 254016 + 617796 = 504^2 + 786^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a plaindrome in base 15.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 871812.

It is not an unprimeable number, because it can be changed into a prime (871817) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1998 + ... + 2394.

2⁸⁷¹⁸¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 871812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1122758).

871812 is an abundant number, since it is smaller than the sum of its proper divisors (1373704).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

871812 is a wasteful number, since it uses less digits than its factorization.

871812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 468 (or 463 counting only the distinct ones).

The product of its digits is 896, while the sum is 27.

The square root of 871812 is about 933.7087340279. The cubic root of 871812 is about 95.5302573095.

The spelling of 871812 in words is "eight hundred seventy-one thousand, eight hundred twelve".