820828285 has 4 divisors (see below), whose sum is σ = 984993948. Its totient is φ = 656662624.

The previous prime is 820828243. The next prime is 820828319. The reversal of 820828285 is 582828028.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 91126116 + 729702169 = 9546^2 + 27013^2 .

It is a cyclic number.

It is not a de Polignac number, because 820828285 - 2⁷ = 820828157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82082824 + ... + 82082833.

It is an arithmetic number, because the mean of its divisors is an integer number (246248487).

Almost surely, 2^820828285 is an apocalyptic number.

It is an amenable number.

820828285 is a deficient number, since it is larger than the sum of its proper divisors (164165663).

820828285 is a wasteful number, since it uses less digits than its factorization.

820828285 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164165662.

The product of its (nonzero) digits is 163840, while the sum is 43.

The square root of 820828285 is about 28650.1009596825. The cubic root of 820828285 is about 936.3052052917.

The spelling of 820828285 in words is "eight hundred twenty million, eight hundred twenty-eight thousand, two hundred eighty-five".