256291843 has 4 divisors (see below), whose sum is σ = 258829488. Its totient is φ = 253754200.

The previous prime is 256291823. The next prime is 256291873. The reversal of 256291843 is 348192652.

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-256291843 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256291796 and 256291805.

It is not an unprimeable number, because it can be changed into a prime (256291823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1268671 + ... + 1268872.

It is an arithmetic number, because the mean of its divisors is an integer number (64707372).

Almost surely, 2^256291843 is an apocalyptic number.

256291843 is a deficient number, since it is larger than the sum of its proper divisors (2537645).

256291843 is a wasteful number, since it uses less digits than its factorization.

256291843 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2537644.

The product of its digits is 103680, while the sum is 40.

The square root of 256291843 is about 16009.1174959771. The cubic root of 256291843 is about 635.2016165954.

It can be divided in two parts, 25629 and 1843, that added together give a palindrome (27472).

The spelling of 256291843 in words is "two hundred fifty-six million, two hundred ninety-one thousand, eight hundred forty-three".