256271805 has 48 divisors (see below), whose sum is σ = 459716400. Its totient is φ = 131963904.

The previous prime is 256271803. The next prime is 256271843. The reversal of 256271805 is 508172652.

It is a happy number.

256271805 is a `hidden beast` number, since 25 + 627 + 1 + 8 + 0 + 5 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 14220441 + 242051364 = 3771^2 + 15558^2 .

It is not a de Polignac number, because 256271805 - 2¹ = 256271803 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 256271805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256271803) 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 47 ways as a sum of consecutive naturals, for example, 247569 + ... + 248601.

It is an arithmetic number, because the mean of its divisors is an integer number (9577425).

Almost surely, 2^256271805 is an apocalyptic number.

It is an amenable number.

256271805 is a deficient number, since it is larger than the sum of its proper divisors (203444595).

256271805 is a wasteful number, since it uses less digits than its factorization.

256271805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1230 (or 1227 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The square root of 256271805 is about 16008.4916528697. The cubic root of 256271805 is about 635.1850618979.

The spelling of 256271805 in words is "two hundred fifty-six million, two hundred seventy-one thousand, eight hundred five".