666662888659 has 4 divisors (see below), whose sum is σ = 689651264160. Its totient is φ = 643674513160.

The previous prime is 666662888597. The next prime is 666662888681. The reversal of 666662888659 is 956888266666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 666662888659 - 2¹⁵ = 666662855891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666662888699) 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 3 ways as a sum of consecutive naturals, for example, 11494187707 + ... + 11494187764.

It is an arithmetic number, because the mean of its divisors is an integer number (172412816040).

Almost surely, 2^666662888659 is an apocalyptic number.

666662888659 is a deficient number, since it is larger than the sum of its proper divisors (22988375501).

666662888659 is a wasteful number, since it uses less digits than its factorization.

666662888659 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22988375500.

The product of its digits is 2149908480, while the sum is 76.

The spelling of 666662888659 in words is "six hundred sixty-six billion, six hundred sixty-two million, eight hundred eighty-eight thousand, six hundred fifty-nine".