8666621766 has 96 divisors (see below), whose sum is σ = 21409090560. Its totient is φ = 2508105600.

The previous prime is 8666621741. The next prime is 8666621801. The reversal of 8666621766 is 6671266668.

It is a super-2 number, since 2×8666621766² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4147650 + ... + 4149738.

It is an arithmetic number, because the mean of its divisors is an integer number (223011360).

Almost surely, 2^8666621766 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 8666621766, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10704545280).

8666621766 is an abundant number, since it is smaller than the sum of its proper divisors (12742468794).

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

8666621766 is a wasteful number, since it uses less digits than its factorization.

8666621766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3042 (or 3039 counting only the distinct ones).

The product of its digits is 5225472, while the sum is 54.

The square root of 8666621766 is about 93094.6924695495. The cubic root of 8666621766 is about 2054.0765019526.

The spelling of 8666621766 in words is "eight billion, six hundred sixty-six million, six hundred twenty-one thousand, seven hundred sixty-six".