665516659987 has 2 divisors, whose sum is σ = 665516659988. Its totient is φ = 665516659986.

The previous prime is 665516659981. The next prime is 665516660077. The reversal of 665516659987 is 789956615566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665516659987 - 2⁷ = 665516659859 is a prime.

It is not a weakly prime, because it can be changed into another prime (665516659981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332758329993 + 332758329994.

It is an arithmetic number, because the mean of its divisors is an integer number (332758329994).

Almost surely, 2^665516659987 is an apocalyptic number.

665516659987 is a deficient number, since it is larger than the sum of its proper divisors (1).

665516659987 is an equidigital number, since it uses as much as digits as its factorization.

665516659987 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 734832000, while the sum is 73.

The spelling of 665516659987 in words is "six hundred sixty-five billion, five hundred sixteen million, six hundred fifty-nine thousand, nine hundred eighty-seven".