866646144 has 288 divisors, whose sum is σ = 3126827340. Its totient is φ = 228372480.

The previous prime is 866646127. The next prime is 866646161. The reversal of 866646144 is 441646668.

866646144 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 (866646127) and next prime (866646161).

It can be written as a sum of positive squares in 2 ways, for example, as 864360000 + 2286144 = 29400^2 + 1512^2 .

It is a tau number, because it is divible by the number of its divisors (288).

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

It is a self number, because there is not a number n which added to its sum of digits gives 866646144.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 733234 + ... + 734414.

Almost surely, 2^866646144 is an apocalyptic number.

866646144 is a gapful number since it is divisible by the number (84) 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 866646144, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1563413670).

866646144 is an abundant number, since it is smaller than the sum of its proper divisors (2260181196).

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

866646144 is a wasteful number, since it uses less digits than its factorization.

866646144 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1228 (or 1206 counting only the distinct ones).

The product of its digits is 663552, while the sum is 45.

The square root of 866646144 is about 29438.8543255338. The cubic root of 866646144 is about 953.4119762771.

The spelling of 866646144 in words is "eight hundred sixty-six million, six hundred forty-six thousand, one hundred forty-four".