800820 has 48 divisors (see below), whose sum is σ = 2493120. Its totient is φ = 213408.

The previous prime is 800801. The next prime is 800861. The reversal of 800820 is 28008.

Added to its reverse (28008) it gives a triangular number (828828 = T₁₂₈₇).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 800793 and 800802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 202 + ... + 1281.

It is an arithmetic number, because the mean of its divisors is an integer number (51940).

2⁸⁰⁰⁸²⁰ 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 800820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1246560).

800820 is an abundant number, since it is smaller than the sum of its proper divisors (1692300).

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

800820 is a wasteful number, since it uses less digits than its factorization.

800820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501 (or 1493 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 800820 is about 894.8854675320. The cubic root of 800820 is about 92.8634833653.

Adding to 800820 its reverse (28008), we get a palindrome (828828).

The spelling of 800820 in words is "eight hundred thousand, eight hundred twenty".