256589 has 2 divisors, whose sum is σ = 256590. Its totient is φ = 256588.

The previous prime is 256579. The next prime is 256603. The reversal of 256589 is 985652.

256589 is nontrivially palindromic in base 6.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198025 + 58564 = 445^2 + 242^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256589 is a prime.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 256589.

It is not a weakly prime, because it can be changed into another prime (256579) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128294 + 128295.

It is an arithmetic number, because the mean of its divisors is an integer number (128295).

2²⁵⁶⁵⁸⁹ is an apocalyptic number.

It is an amenable number.

256589 is a deficient number, since it is larger than the sum of its proper divisors (1).

256589 is an equidigital number, since it uses as much as digits as its factorization.

256589 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 21600, while the sum is 35.

The square root of 256589 is about 506.5461479471. The cubic root of 256589 is about 63.5447016138.

The spelling of 256589 in words is "two hundred fifty-six thousand, five hundred eighty-nine".