256081 has 4 divisors (see below), whose sum is σ = 292672. Its totient is φ = 219492.

The previous prime is 256079. The next prime is 256093. The reversal of 256081 is 180652.

It is a happy number.

256081 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, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 256081 - 2¹ = 256079 is a prime.

It is a super-2 number, since 2×256081² = 131154957122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256021) 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, 18285 + ... + 18298.

It is an arithmetic number, because the mean of its divisors is an integer number (73168).

2²⁵⁶⁰⁸¹ is an apocalyptic number.

It is an amenable number.

256081 is a deficient number, since it is larger than the sum of its proper divisors (36591).

256081 is an equidigital number, since it uses as much as digits as its factorization.

256081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36590.

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 256081 is about 506.0444644495. The cubic root of 256081 is about 63.5027382207.

The spelling of 256081 in words is "two hundred fifty-six thousand, eighty-one".