12688857726121 has 4 divisors (see below), whose sum is σ = 12698180914644. Its totient is φ = 12679534537600.

The previous prime is 12688857726079. The next prime is 12688857726133. The reversal of 12688857726121 is 12162775888621.

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 8917008210496 + 3771849515625 = 2986136^2 + 1942125^2 .

It is a cyclic number.

It is not a de Polignac number, because 12688857726121 - 2¹⁵ = 12688857693353 is a prime.

It is a super-2 number, since 2×12688857726121² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12688857726221) 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, 4661592220 + ... + 4661594941.

It is an arithmetic number, because the mean of its divisors is an integer number (3174545228661).

Almost surely, 2^{12688857726121} is an apocalyptic number.

It is an amenable number.

12688857726121 is a deficient number, since it is larger than the sum of its proper divisors (9323188523).

12688857726121 is an equidigital number, since it uses as much as digits as its factorization.

12688857726121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9323188522.

The product of its digits is 36126720, while the sum is 64.

The spelling of 12688857726121 in words is "twelve trillion, six hundred eighty-eight billion, eight hundred fifty-seven million, seven hundred twenty-six thousand, one hundred twenty-one".