12721813440 has 224 divisors, whose sum is σ = 46243768320. Its totient is φ = 2902695936.

The previous prime is 12721813421. The next prime is 12721813469. The reversal of 12721813440 is 4431812721.

It is a tau number, because it is divible by the number of its divisors (224).

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 31 ways as a sum of consecutive naturals, for example, 4830364 + ... + 4832996.

Almost surely, 2^12721813440 is an apocalyptic number.

12721813440 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 12721813440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23121884160).

12721813440 is an abundant number, since it is smaller than the sum of its proper divisors (33521954880).

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

12721813440 is a wasteful number, since it uses less digits than its factorization.

12721813440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3379 (or 3369 counting only the distinct ones).

The product of its (nonzero) digits is 10752, while the sum is 33.

The spelling of 12721813440 in words is "twelve billion, seven hundred twenty-one million, eight hundred thirteen thousand, four hundred forty".