28056123656 has 64 divisors (see below), whose sum is σ = 58816454400. Its totient is φ = 12436200000.

The previous prime is 28056123643. The next prime is 28056123671. The reversal of 28056123656 is 65632165082.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2488031 + ... + 2499281.

It is an arithmetic number, because the mean of its divisors is an integer number (919007100).

Almost surely, 2^28056123656 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 28056123656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29408227200).

28056123656 is an abundant number, since it is smaller than the sum of its proper divisors (30760330744).

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

28056123656 is a wasteful number, since it uses less digits than its factorization.

28056123656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11970 (or 11966 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 44.

The spelling of 28056123656 in words is "twenty-eight billion, fifty-six million, one hundred twenty-three thousand, six hundred fifty-six".