31099 has 4 divisors (see below), whose sum is σ = 31464. Its totient is φ = 30736.

The previous prime is 31091. The next prime is 31121. The reversal of 31099 is 99013.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 31099 - 2³ = 31091 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24 + ... + 250.

It is an arithmetic number, because the mean of its divisors is an integer number (7866).

2³¹⁰⁹⁹ is an apocalyptic number.

31099 is a deficient number, since it is larger than the sum of its proper divisors (365).

31099 is a wasteful number, since it uses less digits than its factorization.

31099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364.

The product of its (nonzero) digits is 243, while the sum is 22.

The square root of 31099 is about 176.3490856228. The cubic root of 31099 is about 31.4472114927.

The spelling of 31099 in words is "thirty-one thousand, ninety-nine".