256066717 has 2 divisors, whose sum is σ = 256066718. Its totient is φ = 256066716.

The previous prime is 256066709. The next prime is 256066721. The reversal of 256066717 is 717660652.

It is a happy number.

256066717 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 160300921 + 95765796 = 12661^2 + 9786^2 .

It is a cyclic number.

It is not a de Polignac number, because 256066717 - 2³ = 256066709 is a prime.

It is a Chen prime.

It is equal to p_13992934 and since 256066717 and 13992934 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256066717.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256066747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128033358 + 128033359.

It is an arithmetic number, because the mean of its divisors is an integer number (128033359).

Almost surely, 2^256066717 is an apocalyptic number.

It is an amenable number.

256066717 is a deficient number, since it is larger than the sum of its proper divisors (1).

256066717 is an equidigital number, since it uses as much as digits as its factorization.

256066717 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 105840, while the sum is 40.

The square root of 256066717 is about 16002.0847704291. The cubic root of 256066717 is about 635.0155757024.

It can be divided in two parts, 25606 and 6717, that added together give a palindrome (32323).

The spelling of 256066717 in words is "two hundred fifty-six million, sixty-six thousand, seven hundred seventeen".