256507316516765 has 16 divisors (see below), whose sum is σ = 309178057088880. Its totient is φ = 204293888409600.

The previous prime is 256507316516747. The next prime is 256507316516771. The reversal of 256507316516765 is 567615613705652.

It can be written as a sum of positive squares in 8 ways, for example, as 2873089410361 + 253634227106404 = 1695019^2 + 15925898^2 .

It is not a de Polignac number, because 256507316516765 - 2¹⁰ = 256507316515741 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53103980 + ... + 57732549.

It is an arithmetic number, because the mean of its divisors is an integer number (19323628568055).

Almost surely, 2^{256507316516765} is an apocalyptic number.

It is an amenable number.

256507316516765 is a deficient number, since it is larger than the sum of its proper divisors (52670740572115).

256507316516765 is a wasteful number, since it uses less digits than its factorization.

256507316516765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110838592.

The product of its (nonzero) digits is 238140000, while the sum is 65.

The spelling of 256507316516765 in words is "two hundred fifty-six trillion, five hundred seven billion, three hundred sixteen million, five hundred sixteen thousand, seven hundred sixty-five".