66885544558866 has 16 divisors (see below), whose sum is σ = 145932097219488. Its totient is φ = 20268346836000.

The previous prime is 66885544558849. The next prime is 66885544558867.

66885544558866 is nontrivially palindromic in base 10.

It is a Curzon number.

It is a zygodrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (66885544558867) 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, 506708670835 + ... + 506708670966.

It is an arithmetic number, because the mean of its divisors is an integer number (9120756076218).

Almost surely, 2^{66885544558866} is an apocalyptic number.

66885544558866 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

66885544558866 is an abundant number, since it is smaller than the sum of its proper divisors (79046552660622).

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

66885544558866 is a wasteful number, since it uses less digits than its factorization.

66885544558866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1013417341817.

The product of its digits is 53084160000, while the sum is 84.

The spelling of 66885544558866 in words is "sixty-six trillion, eight hundred eighty-five billion, five hundred forty-four million, five hundred fifty-eight thousand, eight hundred sixty-six".