666594399744 has 960 divisors, whose sum is σ = 2571727065600. Its totient is φ = 165554896896.

The previous prime is 666594399739. The next prime is 666594399817. The reversal of 666594399744 is 447993495666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3991583149 + ... + 3991583315.

It is an arithmetic number, because the mean of its divisors is an integer number (2678882360).

Almost surely, 2^666594399744 is an apocalyptic number.

666594399744 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 666594399744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1285863532800).

666594399744 is an abundant number, since it is smaller than the sum of its proper divisors (1905132665856).

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

666594399744 is a wasteful number, since it uses less digits than its factorization.

666594399744 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400 (or 211 counting only the distinct ones).

The product of its digits is 1058158080, while the sum is 72.

The spelling of 666594399744 in words is "six hundred sixty-six billion, five hundred ninety-four million, three hundred ninety-nine thousand, seven hundred forty-four".