8081891784 has 48 divisors (see below), whose sum is σ = 22114130220. Its totient is φ = 2666188800.

The previous prime is 8081891773. The next prime is 8081891789. The reversal of 8081891784 is 4871981808.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 6868762884 + 1213128900 = 82878^2 + 34830^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 8081891784.

It is not an unprimeable number, because it can be changed into a prime (8081891789) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 571617 + ... + 585584.

Almost surely, 2^8081891784 is an apocalyptic number.

It is an amenable number.

8081891784 is an abundant number, since it is smaller than the sum of its proper divisors (14032238436).

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

8081891784 is a wasteful number, since it uses less digits than its factorization.

8081891784 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1157310 (or 1157303 counting only the distinct ones).

The product of its (nonzero) digits is 1032192, while the sum is 54.

The square root of 8081891784 is about 89899.3425115000. The cubic root of 8081891784 is about 2006.8011612203.

The spelling of 8081891784 in words is "eight billion, eighty-one million, eight hundred ninety-one thousand, seven hundred eighty-four".