28728334680 has 128 divisors (see below), whose sum is σ = 91303718400. Its totient is φ = 7206377472.

The previous prime is 28728334669. The next prime is 28728334681. The reversal of 28728334680 is 8643382782.

It is a happy number.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28728334681) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6768639 + ... + 6772881.

It is an arithmetic number, because the mean of its divisors is an integer number (713310300).

Almost surely, 2^28728334680 is an apocalyptic number.

28728334680 is a gapful number since it is divisible by the number (20) 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 28728334680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45651859200).

28728334680 is an abundant number, since it is smaller than the sum of its proper divisors (62575383720).

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

28728334680 is a wasteful number, since it uses less digits than its factorization.

28728334680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7593 (or 7589 counting only the distinct ones).

The product of its (nonzero) digits is 3096576, while the sum is 51.

The spelling of 28728334680 in words is "twenty-eight billion, seven hundred twenty-eight million, three hundred thirty-four thousand, six hundred eighty".