99999857 has 4 divisors (see below), whose sum is σ = 100032420.
Its totient is φ = 99967296.
The previous prime is 99999847. The next prime is 99999931. The reversal of 99999857 is 75899999.
It is a semiprime because it is the product of two primes.
It can be written as a sum of positive squares in 2 ways, for example, as 29170801 + 70829056 = 5401^2 + 8416^2
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-99999857 is a prime.
It is a Duffinian number.
It is a junction number, because it is equal to n+sod(n) for n = 99999793 and 99999802.
It is not an unprimeable number, because it can be changed into a prime (99999827) 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, 11132 + ... + 17997.
It is an arithmetic number, because the mean of its divisors is an integer number (25008105).
Almost surely, 299999857 is an apocalyptic number.
It is an amenable number.
99999857 is a deficient number, since it is larger than the sum of its proper divisors (32563).
99999857 is a wasteful number, since it uses less digits than its factorization.
99999857 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 32562.
The product of its digits is 16533720, while the sum is 65.
The square root of 99999857 is about 9999.9928499974.
The cubic root of 99999857 is about 464.1586621121.
The spelling of 99999857 in words is "ninety-nine million, nine hundred ninety-nine thousand, eight hundred fifty-seven".