20681844860 has 48 divisors (see below), whose sum is σ = 44901353280. Its totient is φ = 7995801600.

The previous prime is 20681844829. The next prime is 20681844863. The reversal of 20681844860 is 6844818602.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20681844863) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 19196 + ... + 204284.

It is an arithmetic number, because the mean of its divisors is an integer number (935444860).

Almost surely, 2^20681844860 is an apocalyptic number.

20681844860 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 20681844860, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22450676640).

20681844860 is an abundant number, since it is smaller than the sum of its proper divisors (24219508420).

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

20681844860 is a wasteful number, since it uses less digits than its factorization.

20681844860 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185286 (or 185284 counting only the distinct ones).

The product of its (nonzero) digits is 589824, while the sum is 47.

The spelling of 20681844860 in words is "twenty billion, six hundred eighty-one million, eight hundred forty-four thousand, eight hundred sixty".