666243342666 has 64 divisors (see below), whose sum is σ = 1654528982400. Its totient is φ = 196967721600.

The previous prime is 666243342641. The next prime is 666243342679.

666243342666 is nontrivially palindromic in base 10.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 13653961 + ... + 13702668.

It is an arithmetic number, because the mean of its divisors is an integer number (25852015350).

Almost surely, 2^666243342666 is an apocalyptic number.

666243342666 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

666243342666 is an abundant number, since it is smaller than the sum of its proper divisors (988285639734).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

666243342666 is a wasteful number, since it uses less digits than its factorization.

666243342666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27356692 (or 27356686 counting only the distinct ones).

The product of its digits is 26873856, while the sum is 54.

The spelling of 666243342666 in words is "six hundred sixty-six billion, two hundred forty-three million, three hundred forty-two thousand, six hundred sixty-six".