12438721872 has 60 divisors (see below), whose sum is σ = 34946701140. Its totient is φ = 4130095104.

The previous prime is 12438721871. The next prime is 12438722003. The reversal of 12438721872 is 27812783421.

It can be written as a sum of positive squares in 2 ways, for example, as 12196110096 + 242611776 = 110436^2 + 15576^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12438721871) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 131047 + ... + 205062.

It is an arithmetic number, because the mean of its divisors is an integer number (582445019).

Almost surely, 2^12438721872 is an apocalyptic number.

12438721872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

12438721872 is an abundant number, since it is smaller than the sum of its proper divisors (22507979268).

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

12438721872 is a wasteful number, since it uses less digits than its factorization.

12438721872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 336380 (or 336371 counting only the distinct ones).

The product of its digits is 301056, while the sum is 45.

The spelling of 12438721872 in words is "twelve billion, four hundred thirty-eight million, seven hundred twenty-one thousand, eight hundred seventy-two".