256843 has 4 divisors (see below), whose sum is σ = 259488. Its totient is φ = 254200.

The previous prime is 256831. The next prime is 256873. The reversal of 256843 is 348652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256843 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256813) 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, 1171 + ... + 1372.

It is an arithmetic number, because the mean of its divisors is an integer number (64872).

2²⁵⁶⁸⁴³ is an apocalyptic number.

256843 is a deficient number, since it is larger than the sum of its proper divisors (2645).

256843 is a wasteful number, since it uses less digits than its factorization.

256843 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2644.

The product of its digits is 5760, while the sum is 28.

The square root of 256843 is about 506.7968034627. The cubic root of 256843 is about 63.5656625427.

Subtracting 256843 from its reverse (348652), we obtain a square (91809 = 303²).

The spelling of 256843 in words is "two hundred fifty-six thousand, eight hundred forty-three".