8687991666 has 16 divisors (see below), whose sum is σ = 17529754464. Its totient is φ = 2870368704.

The previous prime is 8687991647. The next prime is 8687991667. The reversal of 8687991666 is 6661997868.

It is a junction number, because it is equal to n+sod(n) for n = 8687991597 and 8687991606.

It is not an unprimeable number, because it can be changed into a prime (8687991667) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6406396 + ... + 6407751.

It is an arithmetic number, because the mean of its divisors is an integer number (1095609654).

Almost surely, 2^8687991666 is an apocalyptic number.

8687991666 is an abundant number, since it is smaller than the sum of its proper divisors (8841762798).

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

8687991666 is a wasteful number, since it uses less digits than its factorization.

8687991666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12814265.

The product of its digits is 47029248, while the sum is 66.

The square root of 8687991666 is about 93209.3968760661. The cubic root of 8687991666 is about 2055.7634099274.

The spelling of 8687991666 in words is "eight billion, six hundred eighty-seven million, nine hundred ninety-one thousand, six hundred sixty-six".