8365720865 has 16 divisors (see below), whose sum is σ = 10308663120. Its totient is φ = 6514974720.

The previous prime is 8365720837. The next prime is 8365720871. The reversal of 8365720865 is 5680275638.

It can be written as a sum of positive squares in 8 ways, for example, as 604815649 + 7760905216 = 24593^2 + 88096^2 .

It is not a de Polignac number, because 8365720865 - 2²⁶ = 8298612001 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 111800 + ... + 170969.

It is an arithmetic number, because the mean of its divisors is an integer number (644291445).

Almost surely, 2^8365720865 is an apocalyptic number.

It is an amenable number.

8365720865 is a deficient number, since it is larger than the sum of its proper divisors (1942942255).

8365720865 is a wasteful number, since it uses less digits than its factorization.

8365720865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 282932.

The product of its (nonzero) digits is 2419200, while the sum is 50.

The square root of 8365720865 is about 91464.3147079778. The cubic root of 8365720865 is about 2030.0237700146.

The spelling of 8365720865 in words is "eight billion, three hundred sixty-five million, seven hundred twenty thousand, eight hundred sixty-five".