256939843 has 2 divisors, whose sum is σ = 256939844. Its totient is φ = 256939842.

The previous prime is 256939829. The next prime is 256939883. The reversal of 256939843 is 348939652.

256939843 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256939843 is a prime.

It is not a weakly prime, because it can be changed into another prime (256939883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128469921 + 128469922.

It is an arithmetic number, because the mean of its divisors is an integer number (128469922).

Almost surely, 2^256939843 is an apocalyptic number.

256939843 is a deficient number, since it is larger than the sum of its proper divisors (1).

256939843 is an equidigital number, since it uses as much as digits as its factorization.

256939843 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1399680, while the sum is 49.

The square root of 256939843 is about 16029.3431867934. The cubic root of 256939843 is about 635.7365071173.

The spelling of 256939843 in words is "two hundred fifty-six million, nine hundred thirty-nine thousand, eight hundred forty-three".