28635806556 has 240 divisors, whose sum is σ = 87214167040. Its totient is φ = 8024365440.

The previous prime is 28635806543. The next prime is 28635806581. The reversal of 28635806556 is 65560853682.

28635806556 is a `hidden beast` number, since 2 + 8 + 6 + 3 + 5 + 80 + 6 + 556 = 666.

It is a super-3 number, since 3×28635806556³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 32429691 + ... + 32430573.

Almost surely, 2^28635806556 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 28635806556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43607083520).

28635806556 is an abundant number, since it is smaller than the sum of its proper divisors (58578360484).

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

28635806556 is a wasteful number, since it uses less digits than its factorization.

28635806556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1166 (or 1155 counting only the distinct ones).

The product of its (nonzero) digits is 10368000, while the sum is 54.

The spelling of 28635806556 in words is "twenty-eight billion, six hundred thirty-five million, eight hundred six thousand, five hundred fifty-six".