12688384186921 has 4 divisors (see below), whose sum is σ = 12688968899844. Its totient is φ = 12687799474000.

The previous prime is 12688384186909. The next prime is 12688384186963. The reversal of 12688384186921 is 12968148388621.

12688384186921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 10948190528025 + 1740193658896 = 3308805^2 + 1319164^2 .

It is a cyclic number.

It is not a de Polignac number, because 12688384186921 - 2¹⁵ = 12688384154153 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12688384186721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 292323910 + ... + 292367311.

It is an arithmetic number, because the mean of its divisors is an integer number (3172242224961).

Almost surely, 2^{12688384186921} is an apocalyptic number.

It is an amenable number.

12688384186921 is a deficient number, since it is larger than the sum of its proper divisors (584712923).

12688384186921 is an equidigital number, since it uses as much as digits as its factorization.

12688384186921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 584712922.

The product of its digits is 63700992, while the sum is 67.

The spelling of 12688384186921 in words is "twelve trillion, six hundred eighty-eight billion, three hundred eighty-four million, one hundred eighty-six thousand, nine hundred twenty-one".