12688391 has 2 divisors, whose sum is σ = 12688392. Its totient is φ = 12688390.

The previous prime is 12688369. The next prime is 12688411. The reversal of 12688391 is 19388621.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 12688391 - 2¹⁴ = 12672007 is a prime.

It is a zygodrome in base 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12681391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6344195 + 6344196.

It is an arithmetic number, because the mean of its divisors is an integer number (6344196).

Almost surely, 2^12688391 is an apocalyptic number.

12688391 is a deficient number, since it is larger than the sum of its proper divisors (1).

12688391 is an equidigital number, since it uses as much as digits as its factorization.

12688391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 38.

The square root of 12688391 is about 3562.0767818788. The cubic root of 12688391 is about 233.2395443925.

The spelling of 12688391 in words is "twelve million, six hundred eighty-eight thousand, three hundred ninety-one".