665717472785 has 16 divisors (see below), whose sum is σ = 799739904000. Its totient is φ = 531988295616.

The previous prime is 665717472757. The next prime is 665717472811. The reversal of 665717472785 is 587274717566.

It is a cyclic number.

It is not a de Polignac number, because 665717472785 - 2²² = 665713278481 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22476416 + ... + 22506014.

It is an arithmetic number, because the mean of its divisors is an integer number (49983744000).

Almost surely, 2^665717472785 is an apocalyptic number.

It is an amenable number.

665717472785 is a deficient number, since it is larger than the sum of its proper divisors (134022431215).

665717472785 is a wasteful number, since it uses less digits than its factorization.

665717472785 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34400.

The product of its digits is 138297600, while the sum is 65.

The spelling of 665717472785 in words is "six hundred sixty-five billion, seven hundred seventeen million, four hundred seventy-two thousand, seven hundred eighty-five".