20281564800 has 576 divisors, whose sum is σ = 84974323200. Its totient is φ = 4508835840.

The previous prime is 20281564799. The next prime is 20281564813. The reversal of 20281564800 is 846518202.

20281564800 is a `hidden beast` number, since 2 + 0 + 2 + 8 + 1 + 5 + 648 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (576).

It is a super-3 number, since 3×20281564800³ (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 (36).

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 71 ways as a sum of consecutive naturals, for example, 7457841 + ... + 7460559.

Almost surely, 2^20281564800 is an apocalyptic number.

20281564800 is a gapful number since it is divisible by the number (20) 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 20281564800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42487161600).

20281564800 is an abundant number, since it is smaller than the sum of its proper divisors (64692758400).

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

20281564800 is a wasteful number, since it uses less digits than its factorization.

20281564800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2793 (or 2773 counting only the distinct ones).

The product of its (nonzero) digits is 30720, while the sum is 36.

The spelling of 20281564800 in words is "twenty billion, two hundred eighty-one million, five hundred sixty-four thousand, eight hundred".