20481809920 has 160 divisors (see below), whose sum is σ = 57694744800. Its totient is φ = 6874890240.

The previous prime is 20481809911. The next prime is 20481809921. The reversal of 20481809920 is 2990818402.

It is a tau number, because it is divible by the number of its divisors (160).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20481809921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 338106 + ... + 394054.

It is an arithmetic number, because the mean of its divisors is an integer number (360592155).

Almost surely, 2^20481809920 is an apocalyptic number.

20481809920 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 20481809920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28847372400).

20481809920 is an abundant number, since it is smaller than the sum of its proper divisors (37212934880).

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

20481809920 is a wasteful number, since it uses less digits than its factorization.

20481809920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55996 (or 55980 counting only the distinct ones).

The product of its (nonzero) digits is 82944, while the sum is 43.

The spelling of 20481809920 in words is "twenty billion, four hundred eighty-one million, eight hundred nine thousand, nine hundred twenty".