820504 has 8 divisors (see below), whose sum is σ = 1538460. Its totient is φ = 410248.

The previous prime is 820489. The next prime is 820537. The reversal of 820504 is 405028.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (19) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

820504 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 (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51274 + ... + 51289.

2⁸²⁰⁵⁰⁴ is an apocalyptic number.

It is an amenable number.

820504 is a deficient number, since it is larger than the sum of its proper divisors (717956).

820504 is a wasteful number, since it uses less digits than its factorization.

820504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 102569 (or 102565 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 820504 is about 905.8167585113. The cubic root of 820504 is about 93.6181886877.

The spelling of 820504 in words is "eight hundred twenty thousand, five hundred four".