9999865 has 8 divisors (see below), whose sum is σ = 12279168. Its totient is φ = 7813680.

The previous prime is 9999863. The next prime is 9999877. The reversal of 9999865 is 5689999.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 9999865 - 2¹ = 9999863 is a prime.

It is a d-powerful number, because it can be written as 9⁵ + 9⁵ + 9⁷ + 9⁷ + 8⁵ + 6⁷ + 5⁵ .

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 (9999863) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23041 + ... + 23470.

It is an arithmetic number, because the mean of its divisors is an integer number (1534896).

Almost surely, 2^9999865 is an apocalyptic number.

It is an amenable number.

9999865 is a deficient number, since it is larger than the sum of its proper divisors (2279303).

9999865 is a wasteful number, since it uses less digits than its factorization.

9999865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46559.

The product of its digits is 1574640, while the sum is 55.

The square root of 9999865 is about 3162.2563147221. The cubic root of 9999865 is about 215.4424995032.

The spelling of 9999865 in words is "nine million, nine hundred ninety-nine thousand, eight hundred sixty-five".