8663971921920 has 1920 divisors, whose sum is σ = 37374232896000. Its totient is φ = 1883510931456.

The previous prime is 8663971921919. The next prime is 8663971921939. The reversal of 8663971921920 is 291291793668.

8663971921920 is a `hidden beast` number, since 8 + 6 + 6 + 397 + 1 + 9 + 219 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (1920).

It is a super-3 number, since 3×8663971921920³ (a number of 40 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 129313013727 + ... + 129313013793.

It is an arithmetic number, because the mean of its divisors is an integer number (19465746300).

Almost surely, 2^{8663971921920} is an apocalyptic number.

8663971921920 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 8663971921920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18687116448000).

8663971921920 is an abundant number, since it is smaller than the sum of its proper divisors (28710260974080).

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

8663971921920 is an frugal number, since it uses more digits than its factorization.

8663971921920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 17635968, while the sum is 63.

The spelling of 8663971921920 in words is "eight trillion, six hundred sixty-three billion, nine hundred seventy-one million, nine hundred twenty-one thousand, nine hundred twenty".