660256047521 has 8 divisors (see below), whose sum is σ = 765206204544. Its totient is φ = 557962856640.

The previous prime is 660256047499. The next prime is 660256047551. The reversal of 660256047521 is 125740652066.

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

It is not a de Polignac number, because 660256047521 - 2⁶ = 660256047457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (660256047551) 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, 664241000 + ... + 664241993.

It is an arithmetic number, because the mean of its divisors is an integer number (95650775568).

Almost surely, 2^660256047521 is an apocalyptic number.

It is an amenable number.

660256047521 is a deficient number, since it is larger than the sum of its proper divisors (104950157023).

660256047521 is a wasteful number, since it uses less digits than its factorization.

660256047521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1328483071.

The product of its (nonzero) digits is 604800, while the sum is 44.

Adding to 660256047521 its reverse (125740652066), we get a palindrome (785996699587).

The spelling of 660256047521 in words is "six hundred sixty billion, two hundred fifty-six million, forty-seven thousand, five hundred twenty-one".