99999931 has 2 divisors, whose sum is σ = 99999932.
Its totient is φ = 99999930.
The previous prime is 99999847. The next prime is 99999941. The reversal of 99999931 is 13999999.
It is a happy number.
It is a strong prime.
It is a cyclic number.
It is not a de Polignac number, because 99999931 - 215 = 99967163 is a prime.
It is a super-2 number, since 2×999999312 = 19999972400009522, which contains 22 as substring.
It is a nialpdrome in base 10.
It is not a weakly prime, because it can be changed into another prime (99999941) 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 as a sum of consecutive naturals, namely, 49999965 + 49999966.
It is an arithmetic number, because the mean of its divisors is an integer number (49999966).
Almost surely, 299999931 is an apocalyptic number.
99999931 is a deficient number, since it is larger than the sum of its proper divisors (1).
99999931 is an equidigital number, since it uses as much as digits as its factorization.
99999931 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 1594323, while the sum is 58.
The square root of 99999931 is about 9999.9965499994.
The cubic root of 99999931 is about 464.1587766047.
The spelling of 99999931 in words is "ninety-nine million, nine hundred ninety-nine thousand, nine hundred thirty-one".