821825 has 12 divisors (see below), whose sum is σ = 1035648. Its totient is φ = 646800.

The previous prime is 821819. The next prime is 821827. The reversal of 821825 is 528128.

It is not a de Polignac number, because 821825 - 2⁴ = 821809 is a prime.

It is a hoax number, since the sum of its digits (26) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 821794 and 821803.

It is not an unprimeable number, because it can be changed into a prime (821827) by changing a digit.

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 in 11 ways as a sum of consecutive naturals, for example, 1544 + ... + 2006.

It is an arithmetic number, because the mean of its divisors is an integer number (86304).

2⁸²¹⁸²⁵ is an apocalyptic number.

It is an amenable number.

821825 is a deficient number, since it is larger than the sum of its proper divisors (213823).

821825 is a wasteful number, since it uses less digits than its factorization.

821825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544 (or 539 counting only the distinct ones).

The product of its digits is 1280, while the sum is 26.

The square root of 821825 is about 906.5456414324. The cubic root of 821825 is about 93.6684030754.

The spelling of 821825 in words is "eight hundred twenty-one thousand, eight hundred twenty-five".