820255 has 4 divisors (see below), whose sum is σ = 984312. Its totient is φ = 656200.

The previous prime is 820247. The next prime is 820271. The reversal of 820255 is 552028.

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

It is not a de Polignac number, because 820255 - 2³ = 820247 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82021 + ... + 82030.

It is an arithmetic number, because the mean of its divisors is an integer number (246078).

2⁸²⁰²⁵⁵ is an apocalyptic number.

820255 is a deficient number, since it is larger than the sum of its proper divisors (164057).

820255 is a wasteful number, since it uses less digits than its factorization.

820255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164056.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 820255 is about 905.6793030648. The cubic root of 820255 is about 93.6087175629.

The spelling of 820255 in words is "eight hundred twenty thousand, two hundred fifty-five".