8109881664 has 112 divisors (see below), whose sum is σ = 21726144000. Its totient is φ = 2669664256.

The previous prime is 8109881653. The next prime is 8109881669. The reversal of 8109881664 is 4661889018.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8109881669) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5635057 + ... + 5636495.

Almost surely, 2^8109881664 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 8109881664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10863072000).

8109881664 is an abundant number, since it is smaller than the sum of its proper divisors (13616262336).

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

8109881664 is a wasteful number, since it uses less digits than its factorization.

8109881664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1800 (or 1790 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 51.

The square root of 8109881664 is about 90054.8814001773. The cubic root of 8109881664 is about 2009.1151987960.

The spelling of 8109881664 in words is "eight billion, one hundred nine million, eight hundred eighty-one thousand, six hundred sixty-four".