861585099 has 16 divisors (see below), whose sum is σ = 1190488320. Its totient is φ = 553605920.

The previous prime is 861585073. The next prime is 861585113. The reversal of 861585099 is 990585168.

It is a cyclic number.

It is not a de Polignac number, because 861585099 - 2⁹ = 861584587 is a prime.

It is not an unprimeable number, because it can be changed into a prime (861581099) 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, 42634 + ... + 59504.

It is an arithmetic number, because the mean of its divisors is an integer number (74405520).

Almost surely, 2^861585099 is an apocalyptic number.

861585099 is a deficient number, since it is larger than the sum of its proper divisors (328903221).

861585099 is a wasteful number, since it uses less digits than its factorization.

861585099 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17490.

The product of its (nonzero) digits is 777600, while the sum is 51.

The square root of 861585099 is about 29352.7698692985. The cubic root of 861585099 is about 951.5524382547.

The spelling of 861585099 in words is "eight hundred sixty-one million, five hundred eighty-five thousand, ninety-nine".