28280785280 has 128 divisors (see below), whose sum is σ = 76962182400. Its totient is φ = 9836738560.

The previous prime is 28280785261. The next prime is 28280785321. The reversal of 28280785280 is 8258708282.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 74591 + ... + 249249.

It is an arithmetic number, because the mean of its divisors is an integer number (601267050).

Almost surely, 2^28280785280 is an apocalyptic number.

28280785280 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 28280785280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38481091200).

28280785280 is an abundant number, since it is smaller than the sum of its proper divisors (48681397120).

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

28280785280 is a wasteful number, since it uses less digits than its factorization.

28280785280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174712 (or 174700 counting only the distinct ones).

The product of its (nonzero) digits is 1146880, while the sum is 50.

The spelling of 28280785280 in words is "twenty-eight billion, two hundred eighty million, seven hundred eighty-five thousand, two hundred eighty".