256161064 has 16 divisors (see below), whose sum is σ = 493283700. Its totient is φ = 124618752.

The previous prime is 256161047. The next prime is 256161077. The reversal of 256161064 is 460161652.

It can be written as a sum of positive squares in 2 ways, for example, as 186104164 + 70056900 = 13642^2 + 8370^2 .

It is a super-2 number, since 2×256161064² = 131236981419224192, which contains 22 as substring.

It is an unprimeable number.

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 in 3 ways as a sum of consecutive naturals, for example, 432409 + ... + 433000.

Almost surely, 2^256161064 is an apocalyptic number.

It is an amenable number.

256161064 is a deficient number, since it is larger than the sum of its proper divisors (237122636).

256161064 is a wasteful number, since it uses less digits than its factorization.

256161064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 865452 (or 865448 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 31.

The square root of 256161064 is about 16005.0324585738. The cubic root of 256161064 is about 635.0935559760.

The spelling of 256161064 in words is "two hundred fifty-six million, one hundred sixty-one thousand, sixty-four".