666667666667 has 8 divisors (see below), whose sum is σ = 673337346672. Its totient is φ = 659999340000.

The previous prime is 666667666663. The next prime is 666667666697. The reversal of 666667666667 is 766666766666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 666667666667 - 2² = 666667666663 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 666667666594 and 666667666603.

It is not an unprimeable number, because it can be changed into a prime (666667666661) 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 7 ways as a sum of consecutive naturals, for example, 666668 + ... + 1333334.

It is an arithmetic number, because the mean of its divisors is an integer number (84167168334).

Almost surely, 2^666667666667 is an apocalyptic number.

666667666667 is a deficient number, since it is larger than the sum of its proper divisors (6669680005).

666667666667 is a wasteful number, since it uses less digits than its factorization.

666667666667 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 676669.

The product of its digits is 2962842624, while the sum is 74.

Subtracting 666667666667 from its reverse (766666766666), we obtain a palindrome (99999099999).

The spelling of 666667666667 in words is "six hundred sixty-six billion, six hundred sixty-seven million, six hundred sixty-six thousand, six hundred sixty-seven".