256911073 has 2 divisors, whose sum is σ = 256911074. Its totient is φ = 256911072.

The previous prime is 256911047. The next prime is 256911097. The reversal of 256911073 is 370119652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 157051024 + 99860049 = 12532^2 + 9993^2 .

It is a cyclic number.

It is not a de Polignac number, because 256911073 - 2⁵ = 256911041 is a prime.

It is a super-5 number, since 5×256911073⁵ (a number of 43 digits) contains 55555 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (256911023) 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 as a sum of consecutive naturals, namely, 128455536 + 128455537.

It is an arithmetic number, because the mean of its divisors is an integer number (128455537).

Almost surely, 2^256911073 is an apocalyptic number.

It is an amenable number.

256911073 is a deficient number, since it is larger than the sum of its proper divisors (1).

256911073 is an equidigital number, since it uses as much as digits as its factorization.

256911073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11340, while the sum is 34.

The square root of 256911073 is about 16028.4457449873. The cubic root of 256911073 is about 635.7127780584.

The spelling of 256911073 in words is "two hundred fifty-six million, nine hundred eleven thousand, seventy-three".