865931398836 has 144 divisors (see below), whose sum is σ = 2491884876096. Its totient is φ = 232552190976.

The previous prime is 865931398811. The next prime is 865931398837. The reversal of 865931398836 is 638893139568.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (865931398837) 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 47 ways as a sum of consecutive naturals, for example, 7670875 + ... + 7782941.

It is an arithmetic number, because the mean of its divisors is an integer number (17304756084).

Almost surely, 2^865931398836 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 865931398836, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1245942438048).

865931398836 is an abundant number, since it is smaller than the sum of its proper divisors (1625953477260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

865931398836 is a wasteful number, since it uses less digits than its factorization.

865931398836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112878 (or 112869 counting only the distinct ones).

The product of its digits is 201553920, while the sum is 69.

The spelling of 865931398836 in words is "eight hundred sixty-five billion, nine hundred thirty-one million, three hundred ninety-eight thousand, eight hundred thirty-six".