256805339013 has 6 divisors (see below), whose sum is σ = 370941045254. Its totient is φ = 171203559336.

The previous prime is 256805338991. The next prime is 256805339047. The reversal of 256805339013 is 310933508652.

It is a happy number.

256805339013 is a `hidden beast` number, since 2 + 568 + 0 + 53 + 39 + 0 + 1 + 3 = 666.

It can be written as a sum of positive squares in only one way, i.e., 256231353249 + 573985764 = 506193^2 + 23958^2 .

It is not a de Polignac number, because 256805339013 - 2¹⁷ = 256805207941 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256805339013.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256805339083) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14266963270 + ... + 14266963287.

Almost surely, 2^256805339013 is an apocalyptic number.

It is an amenable number.

256805339013 is a deficient number, since it is larger than the sum of its proper divisors (114135706241).

256805339013 is a wasteful number, since it uses less digits than its factorization.

256805339013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28533926563 (or 28533926560 counting only the distinct ones).

The product of its (nonzero) digits is 583200, while the sum is 45.

The spelling of 256805339013 in words is "two hundred fifty-six billion, eight hundred five million, three hundred thirty-nine thousand, thirteen".