256355791 has 2 divisors, whose sum is σ = 256355792. Its totient is φ = 256355790.

The previous prime is 256355789. The next prime is 256355849. The reversal of 256355791 is 197553652.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256355791 - 2¹ = 256355789 is a prime.

Together with 256355789, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256355731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128177895 + 128177896.

It is an arithmetic number, because the mean of its divisors is an integer number (128177896).

Almost surely, 2^256355791 is an apocalyptic number.

256355791 is a deficient number, since it is larger than the sum of its proper divisors (1).

256355791 is an equidigital number, since it uses as much as digits as its factorization.

256355791 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 283500, while the sum is 43.

The square root of 256355791 is about 16011.1146082963. The cubic root of 256355791 is about 635.2544424345.

The spelling of 256355791 in words is "two hundred fifty-six million, three hundred fifty-five thousand, seven hundred ninety-one".