666707666 has 16 divisors (see below), whose sum is σ = 1069378200. Its totient is φ = 310636800.

The previous prime is 666707641. The next prime is 666707677.

666707666 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in 4 ways, for example, as 599221441 + 67486225 = 24479^2 + 8215^2 .

It is a super-2 number, since 2×666707666² = 888998223806335112, which contains 22 as substring.

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 7 ways as a sum of consecutive naturals, for example, 93641 + ... + 100508.

Almost surely, 2^666707666 is an apocalyptic number.

666707666 is a deficient number, since it is larger than the sum of its proper divisors (402670534).

666707666 is a wasteful number, since it uses less digits than its factorization.

666707666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194269.

The product of its (nonzero) digits is 2286144, while the sum is 50.

The square root of 666707666 is about 25820.6829111858. The cubic root of 666707666 is about 873.5983724775.

The spelling of 666707666 in words is "six hundred sixty-six million, seven hundred seven thousand, six hundred sixty-six".