6481921320 has 320 divisors, whose sum is σ = 25052227200. Its totient is φ = 1472463360.

The previous prime is 6481921301. The next prime is 6481921321. The reversal of 6481921320 is 231291846.

6481921320 is a `hidden beast` number, since 648 + 1 + 9 + 2 + 1 + 3 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (6481921321) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4104291 + ... + 4105869.

It is an arithmetic number, because the mean of its divisors is an integer number (78288210).

Almost surely, 2^6481921320 is an apocalyptic number.

6481921320 is a gapful number since it is divisible by the number (60) 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 6481921320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12526113600).

6481921320 is an abundant number, since it is smaller than the sum of its proper divisors (18570305880).

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

6481921320 is a wasteful number, since it uses less digits than its factorization.

6481921320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1790 (or 1777 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 6481921320 is about 80510.3802003195. The cubic root of 6481921320 is about 1864.5237442520.

The spelling of 6481921320 in words is "six billion, four hundred eighty-one million, nine hundred twenty-one thousand, three hundred twenty".