666440008344 has 240 divisors, whose sum is σ = 2172468097800. Its totient is φ = 190071636480.

The previous prime is 666440008343. The next prime is 666440008349. The reversal of 666440008344 is 443800044666.

It is a self number, because there is not a number n which added to its sum of digits gives 666440008344.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666440008343) 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 59 ways as a sum of consecutive naturals, for example, 1082947 + ... + 1582925.

Almost surely, 2^666440008344 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666440008344, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1086234048900).

666440008344 is an abundant number, since it is smaller than the sum of its proper divisors (1506028089456).

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

666440008344 is a wasteful number, since it uses less digits than its factorization.

666440008344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500036 (or 500012 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 45.

The spelling of 666440008344 in words is "six hundred sixty-six billion, four hundred forty million, eight thousand, three hundred forty-four".