12691735321 has 2 divisors, whose sum is σ = 12691735322. Its totient is φ = 12691735320.

The previous prime is 12691735319. The next prime is 12691735393. The reversal of 12691735321 is 12353719621.

12691735321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12452104921 + 239630400 = 111589^2 + 15480^2 .

It is a cyclic number.

It is not a de Polignac number, because 12691735321 - 2¹ = 12691735319 is a prime.

It is a super-2 number, since 2×12691735321² (a number of 21 digits) contains 22 as substring.

Together with 12691735319, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (12691735621) 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 as a sum of consecutive naturals, namely, 6345867660 + 6345867661.

It is an arithmetic number, because the mean of its divisors is an integer number (6345867661).

Almost surely, 2^12691735321 is an apocalyptic number.

It is an amenable number.

12691735321 is a deficient number, since it is larger than the sum of its proper divisors (1).

12691735321 is an equidigital number, since it uses as much as digits as its factorization.

12691735321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 68040, while the sum is 40.

The spelling of 12691735321 in words is "twelve billion, six hundred ninety-one million, seven hundred thirty-five thousand, three hundred twenty-one".