28281689856 has 324 divisors, whose sum is σ = 97928236224. Its totient is φ = 7818854400.

The previous prime is 28281689837. The next prime is 28281689869. The reversal of 28281689856 is 65898618282.

It is a super-2 number, since 2×28281689856² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a zygodrome in base 3.

It is a junction number, because it is equal to n+sod(n) for n = 28281689793 and 28281689802.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3495736 + ... + 3503816.

Almost surely, 2^28281689856 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 28281689856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48964118112).

28281689856 is an abundant number, since it is smaller than the sum of its proper divisors (69646546368).

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

28281689856 is a wasteful number, since it uses less digits than its factorization.

28281689856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8148 (or 8124 counting only the distinct ones).

The product of its digits is 26542080, while the sum is 63.

The spelling of 28281689856 in words is "twenty-eight billion, two hundred eighty-one million, six hundred eighty-nine thousand, eight hundred fifty-six".