12542136721 has 12 divisors (see below), whose sum is σ = 13243297872. Its totient is φ = 11876364504.

The previous prime is 12542136707. The next prime is 12542136727. The reversal of 12542136721 is 12763124521.

12542136721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12542136721 - 2⁵ = 12542136689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12542136727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 883546 + ... + 897628.

It is an arithmetic number, because the mean of its divisors is an integer number (1103608156).

Almost surely, 2^12542136721 is an apocalyptic number.

It is an amenable number.

12542136721 is a deficient number, since it is larger than the sum of its proper divisors (701161151).

12542136721 is a wasteful number, since it uses less digits than its factorization.

12542136721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16588 (or 16569 counting only the distinct ones).

The product of its digits is 20160, while the sum is 34.

The spelling of 12542136721 in words is "twelve billion, five hundred forty-two million, one hundred thirty-six thousand, seven hundred twenty-one".