820770 has 32 divisors (see below), whose sum is σ = 1995840. Its totient is φ = 216000.

The previous prime is 820763. The next prime is 820789. The reversal of 820770 is 77028.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 820770.

It is a congruent number.

It is an unprimeable number.

820770 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3145 + ... + 3395.

It is an arithmetic number, because the mean of its divisors is an integer number (62370).

2⁸²⁰⁷⁷⁰ is an apocalyptic number.

820770 is an abundant number, since it is smaller than the sum of its proper divisors (1175070).

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

820770 is a wasteful number, since it uses less digits than its factorization.

820770 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370.

The product of its (nonzero) digits is 784, while the sum is 24.

The square root of 820770 is about 905.9635754267. The cubic root of 820770 is about 93.6283043190.

Adding to 820770 its reverse (77028), we get a palindrome (897798).

The spelling of 820770 in words is "eight hundred twenty thousand, seven hundred seventy".