8191998720 has 288 divisors, whose sum is σ = 29205489600. Its totient is φ = 2174386176.

The previous prime is 8191998719. The next prime is 8191998733. The reversal of 8191998720 is 278991918.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10125676 + ... + 10126484.

It is an arithmetic number, because the mean of its divisors is an integer number (101407950).

Almost surely, 2^8191998720 is an apocalyptic number.

8191998720 is a gapful number since it is divisible by the number (80) 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 8191998720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14602744800).

8191998720 is an abundant number, since it is smaller than the sum of its proper divisors (21013490880).

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

8191998720 is a wasteful number, since it uses less digits than its factorization.

8191998720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1132 (or 1112 counting only the distinct ones).

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

The square root of 8191998720 is about 90509.6609208100. The cubic root of 8191998720 is about 2015.8735748384.

The spelling of 8191998720 in words is "eight billion, one hundred ninety-one million, nine hundred ninety-eight thousand, seven hundred twenty".