820971 has 12 divisors (see below), whose sum is σ = 1248520. Its totient is φ = 518400.

The previous prime is 820969. The next prime is 820991. The reversal of 820971 is 179028.

It is not a de Polignac number, because 820971 - 2¹ = 820969 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (820901) 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 11 ways as a sum of consecutive naturals, for example, 2230 + ... + 2571.

2⁸²⁰⁹⁷¹ is an apocalyptic number.

820971 is a deficient number, since it is larger than the sum of its proper divisors (427549).

820971 is a wasteful number, since it uses less digits than its factorization.

820971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4826 (or 4823 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 27.

The square root of 820971 is about 906.0745002482. The cubic root of 820971 is about 93.6359466358.

Adding to 820971 its reverse (179028), we get a palindrome (999999).

The spelling of 820971 in words is "eight hundred twenty thousand, nine hundred seventy-one".