30999 has 4 divisors (see below), whose sum is σ = 41336. Its totient is φ = 20664.

The previous prime is 30983. The next prime is 31013. The reversal of 30999 is 99903.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 99903 = 3 ⋅33301.

It is not a de Polignac number, because 30999 - 2⁴ = 30983 is a prime.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

30999 is a modest number, since divided by 999 gives 30 as remainder.

30999 is a lucky number.

It is a plaindrome in base 13.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 30999.

It is not an unprimeable number, because it can be changed into a prime (30949) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5164 + ... + 5169.

It is an arithmetic number, because the mean of its divisors is an integer number (10334).

2³⁰⁹⁹⁹ is an apocalyptic number.

30999 is a deficient number, since it is larger than the sum of its proper divisors (10337).

30999 is a wasteful number, since it uses less digits than its factorization.

30999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10336.

The product of its (nonzero) digits is 2187, while the sum is 30.

The square root of 30999 is about 176.0653287845. The cubic root of 30999 is about 31.4134687374.

The spelling of 30999 in words is "thirty thousand, nine hundred ninety-nine".