864816 has 40 divisors (see below), whose sum is σ = 2291520. Its totient is φ = 280896.

The previous prime is 864811. The next prime is 864817. The reversal of 864816 is 618468.

It is a nude number because it is divisible by every one of its digits.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 864816.

It is not an unprimeable number, because it can be changed into a prime (864811) by changing a digit.

864816 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1855 + ... + 2273.

It is an arithmetic number, because the mean of its divisors is an integer number (57288).

2⁸⁶⁴⁸¹⁶ is an apocalyptic number.

864816 is a gapful number since it is divisible by the number (86) 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 864816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1145760).

864816 is an abundant number, since it is smaller than the sum of its proper divisors (1426704).

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

864816 is a wasteful number, since it uses less digits than its factorization.

864816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 473 (or 467 counting only the distinct ones).

The product of its digits is 9216, while the sum is 33.

The square root of 864816 is about 929.9548376131. The cubic root of 864816 is about 95.2740379257.

The spelling of 864816 in words is "eight hundred sixty-four thousand, eight hundred sixteen".