256185005 has 4 divisors (see below), whose sum is σ = 307422012. Its totient is φ = 204948000.

The previous prime is 256185001. The next prime is 256185011. The reversal of 256185005 is 500581652.

256185005 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 99960004 + 156225001 = 9998^2 + 12499^2 .

It is not a de Polignac number, because 256185005 - 2² = 256185001 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256185001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25618496 + ... + 25618505.

It is an arithmetic number, because the mean of its divisors is an integer number (76855503).

Almost surely, 2^256185005 is an apocalyptic number.

It is an amenable number.

256185005 is a deficient number, since it is larger than the sum of its proper divisors (51237007).

256185005 is an equidigital number, since it uses as much as digits as its factorization.

256185005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51237006.

The product of its (nonzero) digits is 12000, while the sum is 32.

The square root of 256185005 is about 16005.7803621067. The cubic root of 256185005 is about 635.1133407954.

The spelling of 256185005 in words is "two hundred fifty-six million, one hundred eighty-five thousand, five".