256566746 has 16 divisors (see below), whose sum is σ = 396169704. Its totient is φ = 124560384.

The previous prime is 256566733. The next prime is 256566763. The reversal of 256566746 is 647665652.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 247716121 + 8850625 = 15739^2 + 2975^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 256566746.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2195 + ... + 22758.

Almost surely, 2^256566746 is an apocalyptic number.

256566746 is a deficient number, since it is larger than the sum of its proper divisors (139602958).

256566746 is a wasteful number, since it uses less digits than its factorization.

256566746 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25105.

The product of its digits is 1814400, while the sum is 47.

The square root of 256566746 is about 16017.7010210579. The cubic root of 256566746 is about 635.4286448042.

The spelling of 256566746 in words is "two hundred fifty-six million, five hundred sixty-six thousand, seven hundred forty-six".