256603560521 has 32 divisors (see below), whose sum is σ = 321021861888. Its totient is φ = 199263810240.

The previous prime is 256603560517. The next prime is 256603560557. The reversal of 256603560521 is 125065306652.

It is not a de Polignac number, because 256603560521 - 2² = 256603560517 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256603560571) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 58013516 + ... + 58017938.

It is an arithmetic number, because the mean of its divisors is an integer number (10031933184).

Almost surely, 2^256603560521 is an apocalyptic number.

It is an amenable number.

256603560521 is a deficient number, since it is larger than the sum of its proper divisors (64418301367).

256603560521 is a wasteful number, since it uses less digits than its factorization.

256603560521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6861.

The product of its (nonzero) digits is 324000, while the sum is 41.

The spelling of 256603560521 in words is "two hundred fifty-six billion, six hundred three million, five hundred sixty thousand, five hundred twenty-one".