999223809 has 16 divisors (see below), whose sum is σ = 1369327872. Its totient is φ = 647772048.

The previous prime is 999223801. The next prime is 999223811. The reversal of 999223809 is 908322999.

999223809 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 999223809 - 2³ = 999223801 is a prime.

It is not an unprimeable number, because it can be changed into a prime (999223801) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12222 + ... + 46344.

It is an arithmetic number, because the mean of its divisors is an integer number (85582992).

Almost surely, 2^999223809 is an apocalyptic number.

It is an amenable number.

999223809 is a deficient number, since it is larger than the sum of its proper divisors (370104063).

999223809 is a wasteful number, since it uses less digits than its factorization.

999223809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34396.

The product of its (nonzero) digits is 629856, while the sum is 51.

The square root of 999223809 is about 31610.5015619809. The cubic root of 999223809 is about 999.7412026964.

The spelling of 999223809 in words is "nine hundred ninety-nine million, two hundred twenty-three thousand, eight hundred nine".