256406847 has 4 divisors (see below), whose sum is σ = 341875800. Its totient is φ = 170937896.

The previous prime is 256406827. The next prime is 256406863. The reversal of 256406847 is 748604652.

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-256406847 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 256406799 and 256406808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256406827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42734472 + ... + 42734477.

It is an arithmetic number, because the mean of its divisors is an integer number (85468950).

Almost surely, 2^256406847 is an apocalyptic number.

256406847 is a deficient number, since it is larger than the sum of its proper divisors (85468953).

256406847 is an equidigital number, since it uses as much as digits as its factorization.

256406847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85468952.

The product of its (nonzero) digits is 322560, while the sum is 42.

The square root of 256406847 is about 16012.7089213537. The cubic root of 256406847 is about 635.2966122093.

The spelling of 256406847 in words is "two hundred fifty-six million, four hundred six thousand, eight hundred forty-seven".