20561093280 has 1152 divisors, whose sum is σ = 91537205760. Its totient is φ = 4087480320.

The previous prime is 20561093261. The next prime is 20561093327. The reversal of 20561093280 is 8239016502.

20561093280 is a `hidden beast` number, since 2 + 0 + 5 + 610 + 9 + 32 + 8 + 0 = 666.

It is a super-2 number, since 2×20561093280² (a number of 21 digits) contains 22 as substring.

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 191 ways as a sum of consecutive naturals, for example, 231023476 + ... + 231023564.

It is an arithmetic number, because the mean of its divisors is an integer number (79459380).

Almost surely, 2^20561093280 is an apocalyptic number.

20561093280 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 20561093280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45768602880).

20561093280 is an abundant number, since it is smaller than the sum of its proper divisors (70976112480).

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

20561093280 is a wasteful number, since it uses less digits than its factorization.

20561093280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 203 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 20561093280 in words is "twenty billion, five hundred sixty-one million, ninety-three thousand, two hundred eighty".