12781081920 has 112 divisors (see below), whose sum is σ = 40719329280. Its totient is φ = 3396581376.

The previous prime is 12781081903. The next prime is 12781081921. The reversal of 12781081920 is 2918018721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12781081921) 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, 258561 + ... + 303999.

It is an arithmetic number, because the mean of its divisors is an integer number (363565440).

Almost surely, 2^12781081920 is an apocalyptic number.

12781081920 is a gapful number since it is divisible by the number (10) 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 12781081920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20359664640).

12781081920 is an abundant number, since it is smaller than the sum of its proper divisors (27938247360).

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

12781081920 is a wasteful number, since it uses less digits than its factorization.

12781081920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45752 (or 45742 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 39.

The spelling of 12781081920 in words is "twelve billion, seven hundred eighty-one million, eighty-one thousand, nine hundred twenty".