66205856718 has 12 divisors (see below), whose sum is σ = 143446022928. Its totient is φ = 22068618900.

The previous prime is 66205856641. The next prime is 66205856719. The reversal of 66205856718 is 81765850266.

66205856718 is a `hidden beast` number, since 6 + 6 + 20 + 58 + 567 + 1 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66205856719) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1839051558 + ... + 1839051593.

It is an arithmetic number, because the mean of its divisors is an integer number (11953835244).

Almost surely, 2^66205856718 is an apocalyptic number.

66205856718 is an abundant number, since it is smaller than the sum of its proper divisors (77240166210).

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

66205856718 is a wasteful number, since it uses less digits than its factorization.

66205856718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3678103159 (or 3678103156 counting only the distinct ones).

The product of its (nonzero) digits is 4838400, while the sum is 54.

The spelling of 66205856718 in words is "sixty-six billion, two hundred five million, eight hundred fifty-six thousand, seven hundred eighteen".