666173545632 has 144 divisors (see below), whose sum is σ = 2167009633152. Its totient is φ = 190164257280.

The previous prime is 666173545613. The next prime is 666173545649. The reversal of 666173545632 is 236545371666.

It is a tau number, because it is divible by the number of its divisors (144).

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 23 ways as a sum of consecutive naturals, for example, 2103957 + ... + 2399787.

It is an arithmetic number, because the mean of its divisors is an integer number (15048678008).

Almost surely, 2^666173545632 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 666173545632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1083504816576).

666173545632 is an abundant number, since it is smaller than the sum of its proper divisors (1500836087520).

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

666173545632 is a wasteful number, since it uses less digits than its factorization.

666173545632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296971 (or 296960 counting only the distinct ones).

The product of its digits is 16329600, while the sum is 54.

The spelling of 666173545632 in words is "six hundred sixty-six billion, one hundred seventy-three million, five hundred forty-five thousand, six hundred thirty-two".