20840281560 has 256 divisors, whose sum is σ = 80694835200. Its totient is φ = 4685299200.

The previous prime is 20840281559. The next prime is 20840281597. The reversal of 20840281560 is 6518204802.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 63 ways as a sum of consecutive naturals, for example, 438565 + ... + 483755.

It is an arithmetic number, because the mean of its divisors is an integer number (315214200).

Almost surely, 2^20840281560 is an apocalyptic number.

20840281560 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 20840281560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40347417600).

20840281560 is an abundant number, since it is smaller than the sum of its proper divisors (59854553640).

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

20840281560 is a wasteful number, since it uses less digits than its factorization.

20840281560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45279 (or 45269 counting only the distinct ones).

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

The spelling of 20840281560 in words is "twenty billion, eight hundred forty million, two hundred eighty-one thousand, five hundred sixty".