820471 has 8 divisors (see below), whose sum is σ = 876960. Its totient is φ = 767584.

The previous prime is 820459. The next prime is 820481. The reversal of 820471 is 174028.

It is not a de Polignac number, because 820471 - 2⁷ = 820343 is a prime.

It is a super-3 number, since 3×820471³ = 1656955941100041333, which contains 333 as substring.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820411) 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, 4830 + ... + 4996.

It is an arithmetic number, because the mean of its divisors is an integer number (109620).

2⁸²⁰⁴⁷¹ is an apocalyptic number.

820471 is a deficient number, since it is larger than the sum of its proper divisors (56489).

820471 is an equidigital number, since it uses as much as digits as its factorization.

820471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 218 (or 184 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 820471 is about 905.7985427235. The cubic root of 820471 is about 93.6169335886.

Adding to 820471 its reverse (174028), we get a palindrome (994499).

The spelling of 820471 in words is "eight hundred twenty thousand, four hundred seventy-one".