8691991968 has 96 divisors (see below), whose sum is σ = 24956854272. Its totient is φ = 2626937600.

The previous prime is 8691991951. The next prime is 8691992003.

8691991968 is nontrivially palindromic in base 10.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 8691991899 and 8691991908.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 393703 + ... + 415193.

It is an arithmetic number, because the mean of its divisors is an integer number (259967232).

Almost surely, 2^8691991968 is an apocalyptic number.

8691991968 is a gapful number since it is divisible by the number (88) 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 8691991968, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12478427136).

8691991968 is an abundant number, since it is smaller than the sum of its proper divisors (16264862304).

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

8691991968 is a wasteful number, since it uses less digits than its factorization.

8691991968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21898 (or 21890 counting only the distinct ones).

The product of its digits is 15116544, while the sum is 66.

The square root of 8691991968 is about 93230.8530905944. The cubic root of 8691991968 is about 2056.0788803279.

The spelling of 8691991968 in words is "eight billion, six hundred ninety-one million, nine hundred ninety-one thousand, nine hundred sixty-eight".