66666688888872 has 128 divisors (see below), whose sum is σ = 167880281909760. Its totient is φ = 22061044312320.

The previous prime is 66666688888831. The next prime is 66666688888873. The reversal of 66666688888872 is 27888888666666.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (66666688888873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4491449083 + ... + 4491463925.

It is an arithmetic number, because the mean of its divisors is an integer number (1311564702420).

Almost surely, 2^{66666688888872} is an apocalyptic number.

It is an amenable number.

66666688888872 is an abundant number, since it is smaller than the sum of its proper divisors (101213593020888).

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

66666688888872 is a wasteful number, since it uses less digits than its factorization.

66666688888872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17383 (or 17379 counting only the distinct ones).

The product of its digits is 171228266496, while the sum is 93.

The spelling of 66666688888872 in words is "sixty-six trillion, six hundred sixty-six billion, six hundred eighty-eight million, eight hundred eighty-eight thousand, eight hundred seventy-two".