99931 has 4 divisors (see below), whose sum is σ = 107632.
Its totient is φ = 92232.
The previous prime is 99929. The next prime is 99961. The reversal of 99931 is 13999.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 99931 - 21 = 99929 is a prime.
It is a super-2 number, since 2×999312 = 19972409522, which contains 22 as substring.
It is an Ulam number.
It is a Duffinian number.
It is a nialpdrome in base 10.
It is a junction number, because it is equal to n+sod(n) for n = 99893 and 99902.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (99901) 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, 3831 + ... + 3856.
It is an arithmetic number, because the mean of its divisors is an integer number (26908).
299931 is an apocalyptic number.
99931 is a deficient number, since it is larger than the sum of its proper divisors (7701).
99931 is a wasteful number, since it uses less digits than its factorization.
99931 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 7700.
The product of its digits is 2187, while the sum is 31.
The square root of 99931 is about 316.1186486116.
The cubic root of 99931 is about 46.4052102255.
The spelling of 99931 in words is "ninety-nine thousand, nine hundred thirty-one".