865128000 has 448 divisors, whose sum is σ = 3252337920. Its totient is φ = 200704000.

The previous prime is 865127983. The next prime is 865128031. The reversal of 865128000 is 821568.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7655944 + ... + 7656056.

Almost surely, 2^865128000 is an apocalyptic number.

865128000 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 865128000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1626168960).

865128000 is an abundant number, since it is smaller than the sum of its proper divisors (2387209920).

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

865128000 is a wasteful number, since it uses less digits than its factorization.

865128000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 183 (or 163 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 30.

The square root of 865128000 is about 29413.0583244925. The cubic root of 865128000 is about 952.8549389850.

Adding to 865128000 its reverse (821568), we get a palindrome (865949568).

The spelling of 865128000 in words is "eight hundred sixty-five million, one hundred twenty-eight thousand".