256889 has 2 divisors, whose sum is σ = 256890. Its totient is φ = 256888.

The previous prime is 256877. The next prime is 256901. The reversal of 256889 is 988652.

It is a balanced prime because it is at equal distance from previous prime (256877) and next prime (256901).

It can be written as a sum of positive squares in only one way, i.e., 250000 + 6889 = 500^2 + 83^2 .

It is a cyclic number.

It is not a de Polignac number, because 256889 - 2⁴ = 256873 is a prime.

It is a plaindrome in base 10.

It is not a weakly prime, because it can be changed into another prime (256189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128444 + 128445.

It is an arithmetic number, because the mean of its divisors is an integer number (128445).

2²⁵⁶⁸⁸⁹ is an apocalyptic number.

It is an amenable number.

256889 is a deficient number, since it is larger than the sum of its proper divisors (1).

256889 is an equidigital number, since it uses as much as digits as its factorization.

256889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34560, while the sum is 38.

The square root of 256889 is about 506.8421845111. The cubic root of 256889 is about 63.5694571382.

It can be divided in two parts, 25 and 6889, that multiplied together give a square (172225 = 415²).

The spelling of 256889 in words is "two hundred fifty-six thousand, eight hundred eighty-nine".