6480656640 has 576 divisors, whose sum is σ = 24865505280. Its totient is φ = 1593630720.

The previous prime is 6480656627. The next prime is 6480656669. The reversal of 6480656640 is 466560846.

6480656640 is a `hidden beast` number, since 6 + 4 + 80 + 6 + 566 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a super-3 number, since 3×6480656640³ (a number of 30 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

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, 24641149 + ... + 24641411.

It is an arithmetic number, because the mean of its divisors is an integer number (43169280).

Almost surely, 2^6480656640 is an apocalyptic number.

6480656640 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 6480656640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (12432752640).

6480656640 is an abundant number, since it is smaller than the sum of its proper divisors (18384848640).

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

6480656640 is a wasteful number, since it uses less digits than its factorization.

6480656640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347 (or 327 counting only the distinct ones).

The product of its (nonzero) digits is 829440, while the sum is 45.

The square root of 6480656640 is about 80502.5256746644. The cubic root of 6480656640 is about 1864.4024746908.

The spelling of 6480656640 in words is "six billion, four hundred eighty million, six hundred fifty-six thousand, six hundred forty".