999903321 has 12 divisors (see below), whose sum is σ = 1444592448. Its totient is φ = 666469464.

The previous prime is 999903313. The next prime is 999903323. The reversal of 999903321 is 123309999.

999903321 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 999903321 - 2³ = 999903313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (999903323) 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, 62116 + ... + 76538.

It is an arithmetic number, because the mean of its divisors is an integer number (120382704).

Almost surely, 2^999903321 is an apocalyptic number.

It is an amenable number.

999903321 is a deficient number, since it is larger than the sum of its proper divisors (444689127).

999903321 is a wasteful number, since it uses less digits than its factorization.

999903321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22132 (or 22129 counting only the distinct ones).

The product of its (nonzero) digits is 118098, while the sum is 45.

The square root of 999903321 is about 31621.2479355259. The cubic root of 999903321 is about 999.9677726281.

The spelling of 999903321 in words is "nine hundred ninety-nine million, nine hundred three thousand, three hundred twenty-one".