8661856020480 has 1440 divisors, whose sum is σ = 34203556066680. Its totient is φ = 2095125626880.

The previous prime is 8661856020473. The next prime is 8661856020481. The reversal of 8661856020480 is 840206581668.

8661856020480 is a `hidden beast` number, since 8 + 6 + 6 + 1 + 85 + 60 + 20 + 480 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 3950108550144 + 4711747470336 = 1987488^2 + 2170656^2 .

It is a tau number, because it is divible by the number of its divisors (1440).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8661856020481) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 8550696454 + ... + 8550697466.

Almost surely, 2^{8661856020480} is an apocalyptic number.

8661856020480 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 8661856020480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17101778033340).

8661856020480 is an abundant number, since it is smaller than the sum of its proper divisors (25541700046200).

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

8661856020480 is a wasteful number, since it uses less digits than its factorization.

8661856020480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1139 (or 1097 counting only the distinct ones).

The product of its (nonzero) digits is 4423680, while the sum is 54.

The spelling of 8661856020480 in words is "eight trillion, six hundred sixty-one billion, eight hundred fifty-six million, twenty thousand, four hundred eighty".