66666666666667 has 16 divisors (see below), whose sum is σ = 70629026874912. Its totient is φ = 62708841861120.

The previous prime is 66666666666647. The next prime is 66666666666737. The reversal of 66666666666667 is 76666666666666.

66666666666667 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66666666666667 is a prime.

It is a Duffinian number.

It is a plaindrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (66666666666647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1310581968 + ... + 1310632834.

It is an arithmetic number, because the mean of its divisors is an integer number (4414314179682).

Almost surely, 2^{66666666666667} is an apocalyptic number.

66666666666667 is a deficient number, since it is larger than the sum of its proper divisors (3962360208245).

66666666666667 is a wasteful number, since it uses less digits than its factorization.

66666666666667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 93918.

The product of its digits is 91424858112, while the sum is 85.

Subtracting 66666666666667 from its reverse (76666666666666), we obtain a palindrome (9999999999999).

The spelling of 66666666666667 in words is "sixty-six trillion, six hundred sixty-six billion, six hundred sixty-six million, six hundred sixty-six thousand, six hundred sixty-seven".