820831 has 8 divisors (see below), whose sum is σ = 908928. Its totient is φ = 735000.

The previous prime is 820793. The next prime is 820837. The reversal of 820831 is 138028.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 820831 - 2⁹ = 820319 is a prime.

It is a super-2 number, since 2×820831² = 1347527061122, which contains 22 as substring.

It is a Duffinian number.

820831 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 256 + ... + 1306.

It is an arithmetic number, because the mean of its divisors is an integer number (113616).

2⁸²⁰⁸³¹ is an apocalyptic number.

820831 is a deficient number, since it is larger than the sum of its proper divisors (88097).

820831 is a wasteful number, since it uses less digits than its factorization.

820831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1133.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 820831 is about 905.9972406139. The cubic root of 820831 is about 93.6306237609.

Adding to 820831 its reverse (138028), we get a palindrome (958859).

The spelling of 820831 in words is "eight hundred twenty thousand, eight hundred thirty-one".