28272205656 has 160 divisors (see below), whose sum is σ = 83758910400. Its totient is φ = 8884935360.

The previous prime is 28272205649. The next prime is 28272205669. The reversal of 28272205656 is 65650227282.

28272205656 is a `hidden beast` number, since 2 + 82 + 7 + 2 + 2 + 0 + 565 + 6 = 666.

It is a super-2 number, since 2×28272205656² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 2592391 + ... + 2603273.

It is an arithmetic number, because the mean of its divisors is an integer number (523493190).

Almost surely, 2^28272205656 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 28272205656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41879455200).

28272205656 is an abundant number, since it is smaller than the sum of its proper divisors (55486704744).

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

28272205656 is a wasteful number, since it uses less digits than its factorization.

28272205656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11131 (or 11118 counting only the distinct ones).

The product of its (nonzero) digits is 806400, while the sum is 45.

The spelling of 28272205656 in words is "twenty-eight billion, two hundred seventy-two million, two hundred five thousand, six hundred fifty-six".