20681860320 has 288 divisors, whose sum is σ = 77925504384. Its totient is φ = 4953062400.

The previous prime is 20681860271. The next prime is 20681860333. The reversal of 20681860320 is 2306818602.

20681860320 is a `hidden beast` number, since 20 + 6 + 8 + 1 + 8 + 603 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

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 polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1306855 + ... + 1322585.

It is an arithmetic number, because the mean of its divisors is an integer number (270574668).

Almost surely, 2^20681860320 is an apocalyptic number.

20681860320 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 20681860320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38962752192).

20681860320 is an abundant number, since it is smaller than the sum of its proper divisors (57243644064).

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

20681860320 is a wasteful number, since it uses less digits than its factorization.

20681860320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15846 (or 15835 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The spelling of 20681860320 in words is "twenty billion, six hundred eighty-one million, eight hundred sixty thousand, three hundred twenty".