6681673728 has 180 divisors, whose sum is σ = 19521398988. Its totient is φ = 2202009600.

The previous prime is 6681673711. The next prime is 6681673769. The reversal of 6681673728 is 8273761866.

It can be written as a sum of positive squares in 2 ways, for example, as 3451797504 + 3229876224 = 58752^2 + 56832^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16662328 + ... + 16662728.

Almost surely, 2^6681673728 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6681673728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9760699494).

6681673728 is an abundant number, since it is smaller than the sum of its proper divisors (12839725260).

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

6681673728 is a wasteful number, since it uses less digits than its factorization.

6681673728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 519 counting only the distinct ones).

The product of its digits is 4064256, while the sum is 54.

The square root of 6681673728 is about 81741.5055403312. The cubic root of 6681673728 is about 1883.4832179630.

The spelling of 6681673728 in words is "six billion, six hundred eighty-one million, six hundred seventy-three thousand, seven hundred twenty-eight".