666604557667 has 2 divisors, whose sum is σ = 666604557668. Its totient is φ = 666604557666.

The previous prime is 666604557631. The next prime is 666604557683. The reversal of 666604557667 is 766755406666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666604557667 - 2³¹ = 664457074019 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 666604557599 and 666604557608.

It is not a weakly prime, because it can be changed into another prime (666604557167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333302278833 + 333302278834.

It is an arithmetic number, because the mean of its divisors is an integer number (333302278834).

Almost surely, 2^666604557667 is an apocalyptic number.

666604557667 is a deficient number, since it is larger than the sum of its proper divisors (1).

666604557667 is an equidigital number, since it uses as much as digits as its factorization.

666604557667 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 228614400, while the sum is 64.

The spelling of 666604557667 in words is "six hundred sixty-six billion, six hundred four million, five hundred fifty-seven thousand, six hundred sixty-seven".