866320812 has 96 divisors (see below), whose sum is σ = 2636336640. Its totient is φ = 240822720.

The previous prime is 866320811. The next prime is 866320817. The reversal of 866320812 is 218023668.

866320812 is a `hidden beast` number, since 8 + 6 + 632 + 0 + 8 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (866320811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12487 + ... + 43457.

It is an arithmetic number, because the mean of its divisors is an integer number (27461840).

Almost surely, 2^866320812 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 866320812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1318168320).

866320812 is an abundant number, since it is smaller than the sum of its proper divisors (1770015828).

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

866320812 is a wasteful number, since it uses less digits than its factorization.

866320812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31028 (or 31020 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 866320812 is about 29433.3282521702. The cubic root of 866320812 is about 953.2926602803.

The spelling of 866320812 in words is "eight hundred sixty-six million, three hundred twenty thousand, eight hundred twelve".