1680840728 has 96 divisors (see below), whose sum is σ = 3955845600. Its totient is φ = 665054208.

The previous prime is 1680840727. The next prime is 1680840737. The reversal of 1680840728 is 8270480861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680840727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 350813 + ... + 355571.

It is an arithmetic number, because the mean of its divisors is an integer number (41206725).

Almost surely, 2^1680840728 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 1680840728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1977922800).

1680840728 is an abundant number, since it is smaller than the sum of its proper divisors (2275004872).

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

1680840728 is a wasteful number, since it uses less digits than its factorization.

1680840728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4849 (or 4838 counting only the distinct ones).

The product of its (nonzero) digits is 172032, while the sum is 44.

The square root of 1680840728 is about 40998.0576125260. The cubic root of 1680840728 is about 1188.9826599278.

The spelling of 1680840728 in words is "one billion, six hundred eighty million, eight hundred forty thousand, seven hundred twenty-eight".