999971000209 has 16 divisors (see below), whose sum is σ = 1036090078720. Its totient is φ = 964099584000.

The previous prime is 999971000191. The next prime is 999971000257. The reversal of 999971000209 is 902000179999.

It is a cyclic number.

It is not a de Polignac number, because 999971000209 - 2¹¹ = 999970998161 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 999971000209.

It is not an unprimeable number, because it can be changed into a prime (999371000209) 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, 9592849 + ... + 9696529.

It is an arithmetic number, because the mean of its divisors is an integer number (64755629920).

Almost surely, 2^999971000209 is an apocalyptic number.

It is an amenable number.

999971000209 is a deficient number, since it is larger than the sum of its proper divisors (36119078511).

999971000209 is a wasteful number, since it uses less digits than its factorization.

999971000209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 104872.

The product of its (nonzero) digits is 826686, while the sum is 55.

The spelling of 999971000209 in words is "nine hundred ninety-nine billion, nine hundred seventy-one million, two hundred nine", and thus it is an aban number.