820725 has 24 divisors (see below), whose sum is σ = 1404672. Its totient is φ = 422400.

The previous prime is 820723. The next prime is 820733. The reversal of 820725 is 527028.

It is not a de Polignac number, because 820725 - 2¹ = 820723 is a prime.

820725 is a lucky number.

It is a nialpdrome in base 7.

It is a zygodrome in base 7.

It is a junction number, because it is equal to n+sod(n) for n = 820695 and 820704.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 820725.

It is not an unprimeable number, because it can be changed into a prime (820723) 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 23 ways as a sum of consecutive naturals, for example, 2149 + ... + 2501.

It is an arithmetic number, because the mean of its divisors is an integer number (58528).

2⁸²⁰⁷²⁵ is an apocalyptic number.

It is an amenable number.

820725 is a deficient number, since it is larger than the sum of its proper divisors (583947).

820725 is a wasteful number, since it uses less digits than its factorization.

820725 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397 (or 392 counting only the distinct ones).

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 820725 is about 905.9387396508. The cubic root of 820725 is about 93.6265931816.

The spelling of 820725 in words is "eight hundred twenty thousand, seven hundred twenty-five".