66666666668 has 24 divisors (see below), whose sum is σ = 133419831552.
Its totient is φ = 28552893264.
The previous prime is 66666666667. The next prime is 66666666697. The reversal of 66666666668 is 86666666666.
66666666668 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a plaindrome in base 10.
It is a junction number, because it is equal to n+sod(n) for n = 66666666598 and 66666666607.
It is not an unprimeable number, because it can be changed into a prime (66666666667) 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, 728330 + ... + 814737.
It is an arithmetic number, because the mean of its divisors is an integer number (5559159648).
Almost surely, 266666666668 is an apocalyptic number.
It is an amenable number.
66666666668 is an abundant number, since it is smaller than the sum of its proper divisors (66753164884).
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
66666666668 is a wasteful number, since it uses less digits than its factorization.
66666666668 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 1544621 (or 1544619 counting only the distinct ones).
The product of its digits is 483729408, while the sum is 68.
The spelling of 66666666668 in words is "sixty-six billion, six hundred sixty-six million, six hundred sixty-six thousand, six hundred sixty-eight".