820256 has 12 divisors (see below), whose sum is σ = 1614942. Its totient is φ = 410112.

The previous prime is 820247. The next prime is 820271. The reversal of 820256 is 652028.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 739600 + 80656 = 860^2 + 284^2 .

It is a nialpdrome in base 16.

It is an unprimeable number.

820256 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 (5) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12785 + ... + 12848.

2⁸²⁰²⁵⁶ is an apocalyptic number.

It is an amenable number.

820256 is a deficient number, since it is larger than the sum of its proper divisors (794686).

820256 is a wasteful number, since it uses less digits than its factorization.

820256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25643 (or 25635 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 23.

The square root of 820256 is about 905.6798551365. The cubic root of 820256 is about 93.6087556034.

The spelling of 820256 in words is "eight hundred twenty thousand, two hundred fifty-six".