99999993 has 4 divisors (see below), whose sum is σ = 133333328.
Its totient is φ = 66666660.
The previous prime is 99999989. The next prime is 100000007. The reversal of 99999993 is 39999999.
It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.
It is not a de Polignac number, because 99999993 - 22 = 99999989 is a prime.
It is a Duffinian number.
It is a nialpdrome in base 10.
It is not an unprimeable number, because it can be changed into a prime (99992993) 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 in 3 ways as a sum of consecutive naturals, for example, 16666663 + ... + 16666668.
It is an arithmetic number, because the mean of its divisors is an integer number (33333332).
Almost surely, 299999993 is an apocalyptic number.
It is an amenable number.
99999993 is a deficient number, since it is larger than the sum of its proper divisors (33333335).
99999993 is a wasteful number, since it uses less digits than its factorization.
99999993 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 33333334.
The product of its digits is 14348907, while the sum is 66.
The square root of 99999993 is about 9999.9996500000.
Note that the first 3 decimals coincide.
The cubic root of 99999993 is about 464.1588725309.
The spelling of 99999993 in words is "ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-three".