66118689 has 72 divisors (see below), whose sum is σ = 126147840. Its totient is φ = 32985792.

The previous prime is 66118621. The next prime is 66118699. The reversal of 66118689 is 98681166.

It is a happy number.

It is not a de Polignac number, because 66118689 - 2¹⁷ = 65987617 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66118699) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 108624 + ... + 109230.

Almost surely, 2^66118689 is an apocalyptic number.

It is an amenable number.

66118689 is a deficient number, since it is larger than the sum of its proper divisors (60029151).

66118689 is a wasteful number, since it uses less digits than its factorization.

66118689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659 (or 649 counting only the distinct ones).

The product of its digits is 124416, while the sum is 45.

The square root of 66118689 is about 8131.3399264820. The cubic root of 66118689 is about 404.3661048411.

The spelling of 66118689 in words is "sixty-six million, one hundred eighteen thousand, six hundred eighty-nine".