256886281 has 8 divisors (see below), whose sum is σ = 259979400. Its totient is φ = 253811712.

The previous prime is 256886261. The next prime is 256886293. The reversal of 256886281 is 182688652.

It can be written as a sum of positive squares in 4 ways, for example, as 2005056 + 254881225 = 1416^2 + 15965^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256886281 - 2¹⁷ = 256755209 is a prime.

It is a super-2 number, since 2×256886281² = 131981122732021922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256886261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24291 + ... + 33223.

It is an arithmetic number, because the mean of its divisors is an integer number (32497425).

Almost surely, 2^256886281 is an apocalyptic number.

It is an amenable number.

256886281 is a deficient number, since it is larger than the sum of its proper divisors (3093119).

256886281 is a wasteful number, since it uses less digits than its factorization.

256886281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9275.

The product of its digits is 368640, while the sum is 46.

The square root of 256886281 is about 16027.6723512805. The cubic root of 256886281 is about 635.6923285723.

The spelling of 256886281 in words is "two hundred fifty-six million, eight hundred eighty-six thousand, two hundred eighty-one".