656813 has 4 divisors (see below), whose sum is σ = 659100. Its totient is φ = 654528.

The previous prime is 656809. The next prime is 656819. The reversal of 656813 is 318656.

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

It can be written as a sum of positive squares in 2 ways, for example, as 357604 + 299209 = 598^2 + 547^2 .

It is a cyclic number.

It is not a de Polignac number, because 656813 - 2² = 656809 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 (656819) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 638 + ... + 1311.

It is an arithmetic number, because the mean of its divisors is an integer number (164775).

2⁶⁵⁶⁸¹³ is an apocalyptic number.

It is an amenable number.

656813 is a deficient number, since it is larger than the sum of its proper divisors (2287).

656813 is a wasteful number, since it uses less digits than its factorization.

656813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2286.

The product of its digits is 4320, while the sum is 29.

The square root of 656813 is about 810.4400039485. The cubic root of 656813 is about 86.9255098508.

The spelling of 656813 in words is "six hundred fifty-six thousand, eight hundred thirteen".