810820 has 24 divisors (see below), whose sum is σ = 1729728. Its totient is φ = 319200.

The previous prime is 810809. The next prime is 810839. The reversal of 810820 is 28018.

It is a happy number.

810820 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1135 + ... + 1705.

It is an arithmetic number, because the mean of its divisors is an integer number (72072).

2⁸¹⁰⁸²⁰ is an apocalyptic number.

It is an amenable number.

810820 is an abundant number, since it is smaller than the sum of its proper divisors (918908).

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

810820 is a wasteful number, since it uses less digits than its factorization.

810820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 651 (or 649 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 810820 is about 900.4554403190. The cubic root of 810820 is about 93.2484205038.

Adding to 810820 its reverse (28018), we get a palindrome (838838).

It can be divided in two parts, 8108 and 20, that added together give a triangular number (8128 = T₁₂₇).

The spelling of 810820 in words is "eight hundred ten thousand, eight hundred twenty".