820735 has 4 divisors (see below), whose sum is σ = 984888. Its totient is φ = 656584.

The previous prime is 820733. The next prime is 820747. The reversal of 820735 is 537028.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 820735 - 2¹ = 820733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820733) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82069 + ... + 82078.

It is an arithmetic number, because the mean of its divisors is an integer number (246222).

2⁸²⁰⁷³⁵ is an apocalyptic number.

820735 is a deficient number, since it is larger than the sum of its proper divisors (164153).

820735 is a wasteful number, since it uses less digits than its factorization.

820735 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164152.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 820735 is about 905.9442587709. The cubic root of 820735 is about 93.6269734397.

The spelling of 820735 in words is "eight hundred twenty thousand, seven hundred thirty-five".