28280057520 has 640 divisors, whose sum is σ = 111992832000. Its totient is φ = 5797785600.

The previous prime is 28280057503. The next prime is 28280057543. The reversal of 28280057520 is 2575008282.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 20213781 + ... + 20215179.

It is an arithmetic number, because the mean of its divisors is an integer number (174988800).

Almost surely, 2^28280057520 is an apocalyptic number.

28280057520 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 28280057520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55996416000).

28280057520 is an abundant number, since it is smaller than the sum of its proper divisors (83712774480).

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

28280057520 is a wasteful number, since it uses less digits than its factorization.

28280057520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1489 (or 1483 counting only the distinct ones).

The product of its (nonzero) digits is 89600, while the sum is 39.

The spelling of 28280057520 in words is "twenty-eight billion, two hundred eighty million, fifty-seven thousand, five hundred twenty".