666767666 has 16 divisors (see below), whose sum is σ = 1043883288. Its totient is φ = 319113600.

The previous prime is 666767567. The next prime is 666767669.

666767666 is nontrivially palindromic in base 10.

666767666 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 365918641 + 300849025 = 19129^2 + 17345^2 .

It is not an unprimeable number, because it can be changed into a prime (666767669) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72365 + ... + 81056.

Almost surely, 2^666767666 is an apocalyptic number.

666767666 is a deficient number, since it is larger than the sum of its proper divisors (377115622).

666767666 is a wasteful number, since it uses less digits than its factorization.

666767666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 153517.

The product of its digits is 13716864, while the sum is 56.

The square root of 666767666 is about 25821.8447443245. The cubic root of 666767666 is about 873.6245780309.

The spelling of 666767666 in words is "six hundred sixty-six million, seven hundred sixty-seven thousand, six hundred sixty-six".