8161255865 has 16 divisors (see below), whose sum is σ = 11224303488. Its totient is φ = 5580427776.

The previous prime is 8161255849. The next prime is 8161255867. The reversal of 8161255865 is 5685521618.

It is not a de Polignac number, because 8161255865 - 2⁴ = 8161255849 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (8161255867) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 317927 + ... + 342636.

It is an arithmetic number, because the mean of its divisors is an integer number (701518968).

Almost surely, 2^8161255865 is an apocalyptic number.

It is an amenable number.

8161255865 is a deficient number, since it is larger than the sum of its proper divisors (3063047623).

8161255865 is a wasteful number, since it uses less digits than its factorization.

8161255865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 660928.

The product of its digits is 576000, while the sum is 47.

The square root of 8161255865 is about 90339.6693872631. The cubic root of 8161255865 is about 2013.3486966840.

The spelling of 8161255865 in words is "eight billion, one hundred sixty-one million, two hundred fifty-five thousand, eight hundred sixty-five".