256565442 has 32 divisors (see below), whose sum is σ = 588690432. Its totient is φ = 73022544.

The previous prime is 256565429. The next prime is 256565443. The reversal of 256565442 is 244565652.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 256565442.

It is not an unprimeable number, because it can be changed into a prime (256565443) 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 in 15 ways as a sum of consecutive naturals, for example, 568 + ... + 22659.

It is an arithmetic number, because the mean of its divisors is an integer number (18396576).

Almost surely, 2^256565442 is an apocalyptic number.

256565442 is an abundant number, since it is smaller than the sum of its proper divisors (332124990).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256565442 is a wasteful number, since it uses less digits than its factorization.

256565442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23502.

The product of its digits is 288000, while the sum is 39.

The square root of 256565442 is about 16017.6603160387. The cubic root of 256565442 is about 635.4275682807.

The spelling of 256565442 in words is "two hundred fifty-six million, five hundred sixty-five thousand, four hundred forty-two".