666668899987 has 2 divisors, whose sum is σ = 666668899988. Its totient is φ = 666668899986.

The previous prime is 666668899937. The next prime is 666668900003. The reversal of 666668899987 is 789998866666.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-666668899987 is a prime.

It is a super-3 number, since 3×666668899987³ (a number of 36 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 666668899898 and 666668899907.

It is not a weakly prime, because it can be changed into another prime (666668899937) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333334449993 + 333334449994.

It is an arithmetic number, because the mean of its divisors is an integer number (333334449994).

Almost surely, 2^666668899987 is an apocalyptic number.

666668899987 is a deficient number, since it is larger than the sum of its proper divisors (1).

666668899987 is an equidigital number, since it uses as much as digits as its factorization.

666668899987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20316635136, while the sum is 88.

The spelling of 666668899987 in words is "six hundred sixty-six billion, six hundred sixty-eight million, eight hundred ninety-nine thousand, nine hundred eighty-seven".