12689731 has 2 divisors, whose sum is σ = 12689732. Its totient is φ = 12689730.

The previous prime is 12689711. The next prime is 12689771. The reversal of 12689731 is 13798621.

12689731 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is an emirp because it is prime and its reverse (13798621) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12689731 - 2⁷ = 12689603 is a prime.

It is a super-2 number, since 2×12689731² = 322058545704722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12689711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6344865 + 6344866.

It is an arithmetic number, because the mean of its divisors is an integer number (6344866).

Almost surely, 2^12689731 is an apocalyptic number.

12689731 is a deficient number, since it is larger than the sum of its proper divisors (1).

12689731 is an equidigital number, since it uses as much as digits as its factorization.

12689731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18144, while the sum is 37.

The square root of 12689731 is about 3562.2648694335. The cubic root of 12689731 is about 233.2477547844.

The spelling of 12689731 in words is "twelve million, six hundred eighty-nine thousand, seven hundred thirty-one".