664628761732657 has 8 divisors (see below), whose sum is σ = 686070031895552. Its totient is φ = 643187593612800.

The previous prime is 664628761732651. The next prime is 664628761732673. The reversal of 664628761732657 is 756237167826466.

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

It is a cyclic number.

It is not a de Polignac number, because 664628761732657 - 2¹⁹ = 664628761208369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (664628761732651) 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, 12163344 + ... + 38434417.

It is an arithmetic number, because the mean of its divisors is an integer number (85758753986944).

Almost surely, 2^{664628761732657} is an apocalyptic number.

It is an amenable number.

664628761732657 is a deficient number, since it is larger than the sum of its proper divisors (21441270162895).

664628761732657 is a wasteful number, since it uses less digits than its factorization.

664628761732657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51021519.

The product of its digits is 5120962560, while the sum is 76.

The spelling of 664628761732657 in words is "six hundred sixty-four trillion, six hundred twenty-eight billion, seven hundred sixty-one million, seven hundred thirty-two thousand, six hundred fifty-seven".