99664809 has 12 divisors (see below), whose sum is σ = 136213488. Its totient is φ = 64819360.

The previous prime is 99664801. The next prime is 99664813. The reversal of 99664809 is 90846699.

It is not a de Polignac number, because 99664809 - 2³ = 99664801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (99664801) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4839 + ... + 14924.

It is an arithmetic number, because the mean of its divisors is an integer number (11351124).

Almost surely, 2^99664809 is an apocalyptic number.

It is an amenable number.

99664809 is a deficient number, since it is larger than the sum of its proper divisors (36548679).

99664809 is a wasteful number, since it uses less digits than its factorization.

99664809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19848 (or 19807 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 51.

The square root of 99664809 is about 9983.2263822874. The cubic root of 99664809 is about 463.6396965718.

The spelling of 99664809 in words is "ninety-nine million, six hundred sixty-four thousand, eight hundred nine".