8623644666 has 128 divisors (see below), whose sum is σ = 21975023616. Its totient is φ = 2194698240.

The previous prime is 8623644643. The next prime is 8623644691. The reversal of 8623644666 is 6664463268.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9765861 + ... + 9766743.

It is an arithmetic number, because the mean of its divisors is an integer number (171679872).

Almost surely, 2^8623644666 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8623644666, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10987511808).

8623644666 is an abundant number, since it is smaller than the sum of its proper divisors (13351378950).

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

8623644666 is a wasteful number, since it uses less digits than its factorization.

8623644666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1516.

The product of its digits is 5971968, while the sum is 51.

The square root of 8623644666 is about 92863.5809453846. The cubic root of 8623644666 is about 2050.6755390934.

The spelling of 8623644666 in words is "eight billion, six hundred twenty-three million, six hundred forty-four thousand, six hundred sixty-six".