It is a semiprime because it is the product of two primes.
It is a cyclic number.
Almost surely, 2256303303541521 is an apocalyptic number.
It is an amenable number.
256303303541521 is an equidigital number, since it uses as much as digits as its factorization.
256303303541521 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 6927116311970.
The spelling of 256303303541521 in words is "two hundred fifty-six trillion, three hundred three billion, three hundred three million, five hundred forty-one thousand, five hundred twenty-one".