256558142561 has 8 divisors (see below), whose sum is σ = 301133881920. Its totient is φ = 213963547248.

The previous prime is 256558142557. The next prime is 256558142647. The reversal of 256558142561 is 165241855652.

It is a happy number.

256558142561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256558142561 - 2² = 256558142557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256558942561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 495285731 + ... + 495286248.

It is an arithmetic number, because the mean of its divisors is an integer number (37641735240).

Almost surely, 2^256558142561 is an apocalyptic number.

It is an amenable number.

256558142561 is a deficient number, since it is larger than the sum of its proper divisors (44575739359).

256558142561 is an equidigital number, since it uses as much as digits as its factorization.

256558142561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 990572023.

The product of its digits is 2880000, while the sum is 50.

The spelling of 256558142561 in words is "two hundred fifty-six billion, five hundred fifty-eight million, one hundred forty-two thousand, five hundred sixty-one".