256881841 has 4 divisors (see below), whose sum is σ = 265168384. Its totient is φ = 248595300.

The previous prime is 256881829. The next prime is 256881847. The reversal of 256881841 is 148188652.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256881841 - 2¹¹ = 256879793 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256881847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4143225 + ... + 4143286.

It is an arithmetic number, because the mean of its divisors is an integer number (66292096).

Almost surely, 2^256881841 is an apocalyptic number.

It is an amenable number.

256881841 is a deficient number, since it is larger than the sum of its proper divisors (8286543).

256881841 is an equidigital number, since it uses as much as digits as its factorization.

256881841 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8286542.

The product of its digits is 122880, while the sum is 43.

The square root of 256881841 is about 16027.5338402388. The cubic root of 256881841 is about 635.6886661344.

The spelling of 256881841 in words is "two hundred fifty-six million, eight hundred eighty-one thousand, eight hundred forty-one".