256385 has 8 divisors (see below), whose sum is σ = 314496. Its totient is φ = 200560.

The previous prime is 256369. The next prime is 256391. The reversal of 256385 is 583652.

256385 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 256385 - 2⁴ = 256369 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 311 + ... + 780.

It is an arithmetic number, because the mean of its divisors is an integer number (39312).

2²⁵⁶³⁸⁵ is an apocalyptic number.

It is an amenable number.

256385 is a deficient number, since it is larger than the sum of its proper divisors (58111).

256385 is a wasteful number, since it uses less digits than its factorization.

256385 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1143.

The product of its digits is 7200, while the sum is 29.

The square root of 256385 is about 506.3447442208. The cubic root of 256385 is about 63.5278568334.

The spelling of 256385 in words is "two hundred fifty-six thousand, three hundred eighty-five".