660521313656 has 16 divisors (see below), whose sum is σ = 1239029649000. Its totient is φ = 330113407264.

The previous prime is 660521313631. The next prime is 660521313679. The reversal of 660521313656 is 656313125066.

It is a super-3 number, since 3×660521313656³ (a number of 36 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 18387131 + ... + 18423018.

Almost surely, 2^660521313656 is an apocalyptic number.

It is an amenable number.

660521313656 is a deficient number, since it is larger than the sum of its proper divisors (578508335344).

660521313656 is a wasteful number, since it uses less digits than its factorization.

660521313656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36812398 (or 36812394 counting only the distinct ones).

The product of its (nonzero) digits is 583200, while the sum is 44.

The spelling of 660521313656 in words is "six hundred sixty billion, five hundred twenty-one million, three hundred thirteen thousand, six hundred fifty-six".