256563913065 has 16 divisors (see below), whose sum is σ = 424657512000. Its totient is φ = 132115669952.

The previous prime is 256563913061. The next prime is 256563913103. The reversal of 256563913065 is 560319365652.

It is a cyclic number.

It is not a de Polignac number, because 256563913065 - 2² = 256563913061 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 256563912999 and 256563913017.

It is not an unprimeable number, because it can be changed into a prime (256563913061) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 294900615 + ... + 294901484.

It is an arithmetic number, because the mean of its divisors is an integer number (26541094500).

Almost surely, 2^256563913065 is an apocalyptic number.

It is an amenable number.

256563913065 is a deficient number, since it is larger than the sum of its proper divisors (168093598935).

256563913065 is a wasteful number, since it uses less digits than its factorization.

256563913065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 589802136.

The product of its (nonzero) digits is 4374000, while the sum is 51.

The spelling of 256563913065 in words is "two hundred fifty-six billion, five hundred sixty-three million, nine hundred thirteen thousand, sixty-five".