866409984 has 120 divisors (see below), whose sum is σ = 2727997272. Its totient is φ = 262533120.

The previous prime is 866409983. The next prime is 866409989. The reversal of 866409984 is 489904668.

It is a self number, because there is not a number n which added to its sum of digits gives 866409984.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (866409983) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 42142 + ... + 59234.

Almost surely, 2^866409984 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 866409984, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1363998636).

866409984 is an abundant number, since it is smaller than the sum of its proper divisors (1861587288).

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

866409984 is a wasteful number, since it uses less digits than its factorization.

866409984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17128 (or 17109 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The square root of 866409984 is about 29434.8430265901. The cubic root of 866409984 is about 953.3253672157.

The spelling of 866409984 in words is "eight hundred sixty-six million, four hundred nine thousand, nine hundred eighty-four".