166666668899 has 2 divisors, whose sum is σ = 166666668900. Its totient is φ = 166666668898.

The previous prime is 166666668829. The next prime is 166666668901. The reversal of 166666668899 is 998866666661.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 166666668899 - 2⁸ = 166666668643 is a prime.

It is a super-4 number, since 4×166666668899⁴ (a number of 46 digits) contains 4444 as substring.

Together with 166666668901, it forms a pair of twin primes.

It is a Chen prime.

It is a plaindrome in base 10.

It is not a weakly prime, because it can be changed into another prime (166666668829) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 83333334449 + 83333334450.

It is an arithmetic number, because the mean of its divisors is an integer number (83333334450).

Almost surely, 2^166666668899 is an apocalyptic number.

166666668899 is a deficient number, since it is larger than the sum of its proper divisors (1).

166666668899 is an equidigital number, since it uses as much as digits as its factorization.

166666668899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1451188224, while the sum is 77.

The spelling of 166666668899 in words is "one hundred sixty-six billion, six hundred sixty-six million, six hundred sixty-eight thousand, eight hundred ninety-nine".