866617128 has 144 divisors (see below), whose sum is σ = 2581881120. Its totient is φ = 262424448.

The previous prime is 866617127. The next prime is 866617163. The reversal of 866617128 is 821716668.

It is a happy number.

866617128 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (866617127) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 814725 + ... + 815787.

It is an arithmetic number, because the mean of its divisors is an integer number (17929730).

Almost surely, 2^866617128 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 866617128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1290940560).

866617128 is an abundant number, since it is smaller than the sum of its proper divisors (1715263992).

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

866617128 is a wasteful number, since it uses less digits than its factorization.

866617128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1168 (or 1148 counting only the distinct ones).

The product of its digits is 193536, while the sum is 45.

The square root of 866617128 is about 29438.3615033174. The cubic root of 866617128 is about 953.4013358287.

The spelling of 866617128 in words is "eight hundred sixty-six million, six hundred seventeen thousand, one hundred twenty-eight".