1666668507 has 24 divisors (see below), whose sum is σ = 2587161600. Its totient is φ = 951599376.

The previous prime is 1666668473. The next prime is 1666668529. The reversal of 1666668507 is 7058666661.

It is a happy number.

It is not a de Polignac number, because 1666668507 - 2¹¹ = 1666666459 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1666668507.

It is not an unprimeable number, because it can be changed into a prime (1666668547) 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, 207594 + ... + 215472.

It is an arithmetic number, because the mean of its divisors is an integer number (107798400).

Almost surely, 2^1666668507 is an apocalyptic number.

1666668507 is a deficient number, since it is larger than the sum of its proper divisors (920493093).

1666668507 is a wasteful number, since it uses less digits than its factorization.

1666668507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9335 (or 9328 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 51.

The square root of 1666668507 is about 40824.8515857682. The cubic root of 1666668507 is about 1185.6315378878.

The spelling of 1666668507 in words is "one billion, six hundred sixty-six million, six hundred sixty-eight thousand, five hundred seven".