8221981278720 has 640 divisors, whose sum is σ = 29307251001600. Its totient is φ = 1949439098880.

The previous prime is 8221981278697. The next prime is 8221981278733. The reversal of 8221981278720 is 278721891228.

It is a tau number, because it is divible by the number of its divisors (640).

It is a super-2 number, since 2×8221981278720² (a number of 27 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1508894556 + ... + 1508900004.

It is an arithmetic number, because the mean of its divisors is an integer number (45792579690).

Almost surely, 2^{8221981278720} is an apocalyptic number.

8221981278720 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 8221981278720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (14653625500800).

8221981278720 is an abundant number, since it is smaller than the sum of its proper divisors (21085269722880).

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

8221981278720 is a wasteful number, since it uses less digits than its factorization.

8221981278720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5876 (or 5860 counting only the distinct ones).

The product of its (nonzero) digits is 3612672, while the sum is 57.

The spelling of 8221981278720 in words is "eight trillion, two hundred twenty-one billion, nine hundred eighty-one million, two hundred seventy-eight thousand, seven hundred twenty".