99669809 has 2 divisors, whose sum is σ = 99669810. Its totient is φ = 99669808.

The previous prime is 99669769. The next prime is 99669881. The reversal of 99669809 is 90896699.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 91259809 + 8410000 = 9553^2 + 2900^2 .

It is a cyclic number.

It is not a de Polignac number, because 99669809 - 2⁸ = 99669553 is a prime.

It is not a weakly prime, because it can be changed into another prime (99660809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49834904 + 49834905.

It is an arithmetic number, because the mean of its divisors is an integer number (49834905).

Almost surely, 2^99669809 is an apocalyptic number.

It is an amenable number.

99669809 is a deficient number, since it is larger than the sum of its proper divisors (1).

99669809 is an equidigital number, since it uses as much as digits as its factorization.

99669809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1889568, while the sum is 56.

The square root of 99669809 is about 9983.4767991918. The cubic root of 99669809 is about 463.6474497588.

The spelling of 99669809 in words is "ninety-nine million, six hundred sixty-nine thousand, eight hundred nine".