820020 has 48 divisors (see below), whose sum is σ = 2338560. Its totient is φ = 214656.

The previous prime is 819991. The next prime is 820037. The reversal of 820020 is 20028.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 819978 and 820005.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 820020.

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, 4654 + ... + 4826.

It is an arithmetic number, because the mean of its divisors is an integer number (48720).

2⁸²⁰⁰²⁰ 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 820020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1169280).

820020 is an abundant number, since it is smaller than the sum of its proper divisors (1518540).

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

820020 is a wasteful number, since it uses less digits than its factorization.

820020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264 (or 262 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

The square root of 820020 is about 905.5495568990. The cubic root of 820020 is about 93.5997771928.

Adding to 820020 its reverse (20028), we get a palindrome (840048).

The spelling of 820020 in words is "eight hundred twenty thousand, twenty".