666717056895 has 8 divisors (see below), whose sum is σ = 1066747291056. Its totient is φ = 355582430336.

The previous prime is 666717056881. The next prime is 666717056899. The reversal of 666717056895 is 598650717666.

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 666717056895 - 2⁷ = 666717056767 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666717056899) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22223901882 + ... + 22223901911.

It is an arithmetic number, because the mean of its divisors is an integer number (133343411382).

Almost surely, 2^666717056895 is an apocalyptic number.

666717056895 is a deficient number, since it is larger than the sum of its proper divisors (400030234161).

666717056895 is a wasteful number, since it uses less digits than its factorization.

666717056895 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44447803801.

The product of its (nonzero) digits is 114307200, while the sum is 66.

The spelling of 666717056895 in words is "six hundred sixty-six billion, seven hundred seventeen million, fifty-six thousand, eight hundred ninety-five".