12439415721 has 16 divisors (see below), whose sum is σ = 16987345920. Its totient is φ = 8093854080.

The previous prime is 12439415711. The next prime is 12439415741. The reversal of 12439415721 is 12751493421.

It is not a de Polignac number, because 12439415721 - 2¹³ = 12439407529 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12439415721.

It is not an unprimeable number, because it can be changed into a prime (12439415711) 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, 174436 + ... + 235173.

It is an arithmetic number, because the mean of its divisors is an integer number (1061709120).

Almost surely, 2^12439415721 is an apocalyptic number.

It is an amenable number.

12439415721 is a deficient number, since it is larger than the sum of its proper divisors (4547930199).

12439415721 is a wasteful number, since it uses less digits than its factorization.

12439415721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409856.

The product of its digits is 60480, while the sum is 39.

The spelling of 12439415721 in words is "twelve billion, four hundred thirty-nine million, four hundred fifteen thousand, seven hundred twenty-one".