666229999 has 2 divisors, whose sum is σ = 666230000. Its totient is φ = 666229998.

The previous prime is 666229997. The next prime is 666230009. The reversal of 666229999 is 999922666.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 666229999 - 2¹ = 666229997 is a prime.

Together with 666229997, it forms a pair of twin primes.

It is a Chen prime.

It is a zygodrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (666229997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333114999 + 333115000.

It is an arithmetic number, because the mean of its divisors is an integer number (333115000).

Almost surely, 2^666229999 is an apocalyptic number.

666229999 is a deficient number, since it is larger than the sum of its proper divisors (1).

666229999 is an equidigital number, since it uses as much as digits as its factorization.

666229999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5668704, while the sum is 58.

The square root of 666229999 is about 25811.4315565797. The cubic root of 666229999 is about 873.3896909063.

The spelling of 666229999 in words is "six hundred sixty-six million, two hundred twenty-nine thousand, nine hundred ninety-nine".