656801 has 4 divisors (see below), whose sum is σ = 666672. Its totient is φ = 646932.

The previous prime is 656791. The next prime is 656809. The reversal of 656801 is 108656.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 656801 - 2⁶ = 656737 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (656809) 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 3 ways as a sum of consecutive naturals, for example, 4835 + ... + 4968.

It is an arithmetic number, because the mean of its divisors is an integer number (166668).

2⁶⁵⁶⁸⁰¹ is an apocalyptic number.

It is an amenable number.

656801 is a deficient number, since it is larger than the sum of its proper divisors (9871).

656801 is an equidigital number, since it uses as much as digits as its factorization.

656801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9870.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 656801 is about 810.4326005289. The cubic root of 656801 is about 86.9249804700.

The spelling of 656801 in words is "six hundred fifty-six thousand, eight hundred one".