256001 has 4 divisors (see below), whose sum is σ = 260400. Its totient is φ = 251604.

The previous prime is 255989. The next prime is 256019. The reversal of 256001 is 100652.

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 256001 - 2¹⁰ = 254977 is a prime.

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 pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2111 + ... + 2228.

It is an arithmetic number, because the mean of its divisors is an integer number (65100).

It is a Proth number, since it is equal to 125 ⋅ 2¹¹ + 1 and 125 < 2¹¹.

2²⁵⁶⁰⁰¹ is an apocalyptic number.

It is an amenable number.

256001 is a deficient number, since it is larger than the sum of its proper divisors (4399).

256001 is an equidigital number, since it uses as much as digits as its factorization.

256001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4398.

The product of its (nonzero) digits is 60, while the sum is 14.

The square root of 256001 is about 505.9654138377. The cubic root of 256001 is about 63.4961247558.

Adding to 256001 its reverse (100652), we get a palindrome (356653).

The spelling of 256001 in words is "two hundred fifty-six thousand, one".