872820 has 72 divisors (see below), whose sum is σ = 2858856. Its totient is φ = 214272.

The previous prime is 872791. The next prime is 872843. The reversal of 872820 is 28278.

872820 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 19044 + 853776 = 138^2 + 924^2 .

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

872820 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2154 + ... + 2526.

2⁸⁷²⁸²⁰ 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 872820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1429428).

872820 is an abundant number, since it is smaller than the sum of its proper divisors (1986036).

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

872820 is a wasteful number, since it uses less digits than its factorization.

872820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 401 (or 396 counting only the distinct ones).

The product of its (nonzero) digits is 1792, while the sum is 27.

The square root of 872820 is about 934.2483609833. The cubic root of 872820 is about 95.5670608906.

The spelling of 872820 in words is "eight hundred seventy-two thousand, eight hundred twenty".