865231331328 has 1680 divisors, whose sum is σ = 3416924982240. Its totient is φ = 215818960896.

The previous prime is 865231331303. The next prime is 865231331333. The reversal of 865231331328 is 823133132568.

865231331328 is a `hidden beast` number, since 8 + 6 + 5 + 2 + 313 + 3 + 1 + 328 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 9721700308 + ... + 9721700396.

It is an arithmetic number, because the mean of its divisors is an integer number (2033883918).

Almost surely, 2^865231331328 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 865231331328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1708462491120).

865231331328 is an abundant number, since it is smaller than the sum of its proper divisors (2551693650912).

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

865231331328 is a wasteful number, since it uses less digits than its factorization.

865231331328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 137 counting only the distinct ones).

The product of its digits is 622080, while the sum is 45.

The spelling of 865231331328 in words is "eight hundred sixty-five billion, two hundred thirty-one million, three hundred thirty-one thousand, three hundred twenty-eight".