999000921 has 8 divisors (see below), whose sum is σ = 1354577760. Its totient is φ = 654712352.

The previous prime is 999000911. The next prime is 999000941. The reversal of 999000921 is 129000999.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 999000921 - 2¹⁵ = 998968153 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 999000921.

It is not an unprimeable number, because it can be changed into a prime (999000901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2821860 + ... + 2822213.

It is an arithmetic number, because the mean of its divisors is an integer number (169322220).

Almost surely, 2^999000921 is an apocalyptic number.

It is an amenable number.

999000921 is a deficient number, since it is larger than the sum of its proper divisors (355576839).

999000921 is a wasteful number, since it uses less digits than its factorization.

999000921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5644135.

The product of its (nonzero) digits is 13122, while the sum is 39.

The square root of 999000921 is about 31606.9758281301. The cubic root of 999000921 is about 999.6668626985. Note that the first 3 decimals are identical.

The spelling of 999000921 in words is "nine hundred ninety-nine million, nine hundred twenty-one", and thus it is an aban number.