99999665 has 8 divisors (see below), whose sum is σ = 120053760.
Its totient is φ = 79963632.
The previous prime is 99999643. The next prime is 99999677. The reversal of 99999665 is 56699999.
It is a sphenic number, since it is the product of 3 distinct primes.
It is a cyclic number.
It is not a de Polignac number, because 99999665 - 212 = 99995569 is a prime.
It is a super-2 number, since 2×999996652 = 19999866000224450, which contains 22 as substring.
It is a nialpdrome in base 10.
It is a junction number, because it is equal to n+sod(n) for n = 99999598 and 99999607.
It is an unprimeable number.
It is a pernicious number, because its binary representation contains a prime number (19) of ones.
It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16976 + ... + 22094.
It is an arithmetic number, because the mean of its divisors is an integer number (15006720).
Almost surely, 299999665 is an apocalyptic number.
It is an amenable number.
99999665 is a deficient number, since it is larger than the sum of its proper divisors (20054095).
99999665 is a wasteful number, since it uses less digits than its factorization.
99999665 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 9031.
The product of its digits is 10628820, while the sum is 62.
The square root of 99999665 is about 9999.9832499860.
The cubic root of 99999665 is about 464.1583650499.
The spelling of 99999665 in words is "ninety-nine million, nine hundred ninety-nine thousand, six hundred sixty-five".