666684760 has 128 divisors (see below), whose sum is σ = 1791590400. Its totient is φ = 218465280.

The previous prime is 666684703. The next prime is 666684763. The reversal of 666684760 is 67486666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666684763) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 772089 + ... + 772951.

It is an arithmetic number, because the mean of its divisors is an integer number (13996800).

Almost surely, 2^666684760 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 666684760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (895795200).

666684760 is an abundant number, since it is smaller than the sum of its proper divisors (1124905640).

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

666684760 is a wasteful number, since it uses less digits than its factorization.

666684760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1001 (or 997 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 49.

The square root of 666684760 is about 25820.2393482322. The cubic root of 666684760 is about 873.5883676561.

The spelling of 666684760 in words is "six hundred sixty-six million, six hundred eighty-four thousand, seven hundred sixty".