666706670689 has 8 divisors (see below), whose sum is σ = 670414325672. Its totient is φ = 662999281920.

The previous prime is 666706670683. The next prime is 666706670863. The reversal of 666706670689 is 986076607666.

It can be written as a sum of positive squares in 4 ways, for example, as 115333593664 + 551373077025 = 339608^2 + 742545^2 .

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 666706670689 - 2³¹ = 664559187041 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666706670683) 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, 7079737 + ... + 7173289.

It is an arithmetic number, because the mean of its divisors is an integer number (83801790709).

Almost surely, 2^666706670689 is an apocalyptic number.

It is an amenable number.

666706670689 is a deficient number, since it is larger than the sum of its proper divisors (3707654983).

666706670689 is a wasteful number, since it uses less digits than its factorization.

666706670689 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133107.

The product of its (nonzero) digits is 164602368, while the sum is 67.

The spelling of 666706670689 in words is "six hundred sixty-six billion, seven hundred six million, six hundred seventy thousand, six hundred eighty-nine".