256117 has 2 divisors, whose sum is σ = 256118. Its totient is φ = 256116.

The previous prime is 256093. The next prime is 256121. The reversal of 256117 is 711652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 256036 + 81 = 506^2 + 9^2 .

It is a cyclic number.

It is not a de Polignac number, because 256117 - 2⁷ = 255989 is a prime.

It is a zygodrome in base 3.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256147) 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, 128058 + 128059.

It is an arithmetic number, because the mean of its divisors is an integer number (128059).

2²⁵⁶¹¹⁷ is an apocalyptic number.

It is an amenable number.

256117 is a deficient number, since it is larger than the sum of its proper divisors (1).

256117 is an equidigital number, since it uses as much as digits as its factorization.

256117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 420, while the sum is 22.

The square root of 256117 is about 506.0800331963. The cubic root of 256117 is about 63.5057138306.

Adding to 256117 its reverse (711652), we get a palindrome (967769).

Subtracting 256117 from its reverse (711652), we obtain a triangular number (455535 = T₉₅₄).

It can be divided in two parts, 256 and 117, that added together give a palindrome (373).

The spelling of 256117 in words is "two hundred fifty-six thousand, one hundred seventeen".