28173128256 has 336 divisors, whose sum is σ = 104623209600. Its totient is φ = 7038959616.

The previous prime is 28173128201. The next prime is 28173128261. The reversal of 28173128256 is 65282137182.

28173128256 is a `hidden beast` number, since 2 + 81 + 7 + 312 + 8 + 256 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 981760 + ... + 1010048.

It is an arithmetic number, because the mean of its divisors is an integer number (311378600).

Almost surely, 2^28173128256 is an apocalyptic number.

28173128256 is a gapful number since it is divisible by the number (26) 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 28173128256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52311604800).

28173128256 is an abundant number, since it is smaller than the sum of its proper divisors (76450081344).

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

28173128256 is a wasteful number, since it uses less digits than its factorization.

28173128256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28346 (or 28333 counting only the distinct ones).

The product of its digits is 322560, while the sum is 45.

The spelling of 28173128256 in words is "twenty-eight billion, one hundred seventy-three million, one hundred twenty-eight thousand, two hundred fifty-six".