820000 has 60 divisors (see below), whose sum is σ = 2066526. Its totient is φ = 320000.

The previous prime is 819991. The next prime is 820037. The reversal of 820000 is 28.

It is a happy number.

820000 is nontrivially palindromic in base 9.

It can be written as a sum of positive squares in 5 ways, for example, as 24336 + 795664 = 156^2 + 892^2 .

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a nialpdrome in base 10 and base 16.

It is an unprimeable number.

820000 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 9 ways as a sum of consecutive naturals, for example, 19980 + ... + 20020.

2⁸²⁰⁰⁰⁰ is an apocalyptic number.

820000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 820000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1033263).

820000 is an abundant number, since it is smaller than the sum of its proper divisors (1246526).

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

820000 is an equidigital number, since it uses as much as digits as its factorization.

820000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71 (or 48 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 820000 is about 905.5385138137. The cubic root of 820000 is about 93.5990162314.

Adding to 820000 its reverse (28), we get a palindrome (820028).

It can be divided in two parts, 8 and 20000, that multiplied together give a 4-th power (160000 = 20⁴).

The spelling of 820000 in words is "eight hundred twenty thousand".