6481440 has 144 divisors (see below), whose sum is σ = 25316928. Its totient is φ = 1479168.

The previous prime is 6481439. The next prime is 6481457. The reversal of 6481440 is 441846.

6481440 is a `hidden beast` number, since 648 + 14 + 4 + 0 = 666.

6481440 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (144).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9759 + ... + 10401.

It is an arithmetic number, because the mean of its divisors is an integer number (175812).

Almost surely, 2^6481440 is an apocalyptic number.

6481440 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 6481440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12658464).

6481440 is an abundant number, since it is smaller than the sum of its proper divisors (18835488).

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

6481440 is a wasteful number, since it uses less digits than its factorization.

6481440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 671 (or 660 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 27.

The square root of 6481440 is about 2545.8672392723. The cubic root of 6481440 is about 186.4477592566.

The spelling of 6481440 in words is "six million, four hundred eighty-one thousand, four hundred forty".