256261 has 4 divisors (see below), whose sum is σ = 260524. Its totient is φ = 252000.

The previous prime is 256219. The next prime is 256279. The reversal of 256261 is 162652.

256261 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 11236 + 245025 = 106^2 + 495^2 .

It is a cyclic number.

It is not a de Polignac number, because 256261 - 2⁷ = 256133 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2040 + ... + 2161.

It is an arithmetic number, because the mean of its divisors is an integer number (65131).

2²⁵⁶²⁶¹ is an apocalyptic number.

It is an amenable number.

256261 is a deficient number, since it is larger than the sum of its proper divisors (4263).

256261 is an equidigital number, since it uses as much as digits as its factorization.

256261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4262.

The product of its digits is 720, while the sum is 22.

The square root of 256261 is about 506.2222831919. Note that the first 4 decimals coincide. The cubic root of 256261 is about 63.5176134825.

The spelling of 256261 in words is "two hundred fifty-six thousand, two hundred sixty-one".