816864 has 48 divisors (see below), whose sum is σ = 2193408. Its totient is φ = 266112.

The previous prime is 816859. The next prime is 816869. The reversal of 816864 is 468618.

816864 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (816859) and next prime (816869).

It is a tau number, because it is divible by the number of its divisors (48).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816869) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6369 + ... + 6495.

It is an arithmetic number, because the mean of its divisors is an integer number (45696).

2⁸¹⁶⁸⁶⁴ 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 816864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1096704).

816864 is an abundant number, since it is smaller than the sum of its proper divisors (1376544).

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

816864 is a wasteful number, since it uses less digits than its factorization.

816864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207 (or 199 counting only the distinct ones).

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

The square root of 816864 is about 903.8052887652. The cubic root of 816864 is about 93.4795440775.

The spelling of 816864 in words is "eight hundred sixteen thousand, eight hundred sixty-four".