666580608 has 192 divisors, whose sum is σ = 2057182920. Its totient is φ = 206438400.

The previous prime is 666580571. The next prime is 666580609. The reversal of 666580608 is 806085666.

666580608 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 663165504 + 3415104 = 25752^2 + 1848^2 .

It is a tau number, because it is divible by the number of its divisors (192).

It is not an unprimeable number, because it can be changed into a prime (666580609) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1977816 + ... + 1978152.

Almost surely, 2^666580608 is an apocalyptic number.

666580608 is a gapful number since it is divisible by the number (68) 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 666580608, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1028591460).

666580608 is an abundant number, since it is smaller than the sum of its proper divisors (1390602312).

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

666580608 is a wasteful number, since it uses less digits than its factorization.

666580608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 475 (or 460 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 45.

The square root of 666580608 is about 25818.2224020168. Note that the first 3 decimals coincide. The cubic root of 666580608 is about 873.5428735337.

The spelling of 666580608 in words is "six hundred sixty-six million, five hundred eighty thousand, six hundred eight".