8091781992 has 144 divisors (see below), whose sum is σ = 26993044260. Its totient is φ = 2175925248.

The previous prime is 8091781991. The next prime is 8091781993. The reversal of 8091781992 is 2991871908.

It is an interprime number because it is at equal distance from previous prime (8091781991) and next prime (8091781993).

It can be written as a sum of positive squares in 2 ways, for example, as 6523146756 + 1568635236 = 80766^2 + 39606^2 .

It is not an unprimeable number, because it can be changed into a prime (8091781991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 7483 + ... + 127434.

Almost surely, 2^8091781992 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 8091781992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13496522130).

8091781992 is an abundant number, since it is smaller than the sum of its proper divisors (18901262268).

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

8091781992 is a wasteful number, since it uses less digits than its factorization.

8091781992 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134960 (or 134946 counting only the distinct ones).

The product of its (nonzero) digits is 653184, while the sum is 54.

The square root of 8091781992 is about 89954.3328139340. The cubic root of 8091781992 is about 2007.6194345790.

The spelling of 8091781992 in words is "eight billion, ninety-one million, seven hundred eighty-one thousand, nine hundred ninety-two".