66017578657 has 8 divisors (see below), whose sum is σ = 69513116960. Its totient is φ = 62524133280.

The previous prime is 66017578637. The next prime is 66017578667. The reversal of 66017578657 is 75687571066.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66017578657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66017578637) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 458268 + ... + 584845.

It is an arithmetic number, because the mean of its divisors is an integer number (8689139620).

Almost surely, 2^66017578657 is an apocalyptic number.

It is an amenable number.

66017578657 is a deficient number, since it is larger than the sum of its proper divisors (3495538303).

66017578657 is a wasteful number, since it uses less digits than its factorization.

66017578657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1046463.

The product of its (nonzero) digits is 14817600, while the sum is 58.

The spelling of 66017578657 in words is "sixty-six billion, seventeen million, five hundred seventy-eight thousand, six hundred fifty-seven".