256655305 has 8 divisors (see below), whose sum is σ = 308972232. Its totient is φ = 204667008.

The previous prime is 256655303. The next prime is 256655381. The reversal of 256655305 is 503556652.

It can be written as a sum of positive squares in 4 ways, for example, as 14417209 + 242238096 = 3797^2 + 15564^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256655305 - 2¹ = 256655303 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256655303) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80434 + ... + 83563.

It is an arithmetic number, because the mean of its divisors is an integer number (38621529).

Almost surely, 2^256655305 is an apocalyptic number.

It is an amenable number.

256655305 is a deficient number, since it is larger than the sum of its proper divisors (52316927).

256655305 is a wasteful number, since it uses less digits than its factorization.

256655305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 164315.

The product of its (nonzero) digits is 135000, while the sum is 37.

The square root of 256655305 is about 16020.4651929961. The cubic root of 256655305 is about 635.5017465771.

The spelling of 256655305 in words is "two hundred fifty-six million, six hundred fifty-five thousand, three hundred five".