12897691 has 4 divisors (see below), whose sum is σ = 12905584. Its totient is φ = 12889800.

The previous prime is 12897683. The next prime is 12897697. The reversal of 12897691 is 19679821.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 12897691 - 2³ = 12897683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12897697) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 480 + ... + 5101.

It is an arithmetic number, because the mean of its divisors is an integer number (3226396).

Almost surely, 2^12897691 is an apocalyptic number.

12897691 is a deficient number, since it is larger than the sum of its proper divisors (7893).

12897691 is an equidigital number, since it uses as much as digits as its factorization.

12897691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7892.

The product of its digits is 54432, while the sum is 43.

The square root of 12897691 is about 3591.3355454482. The cubic root of 12897691 is about 234.5150160945.

The spelling of 12897691 in words is "twelve million, eight hundred ninety-seven thousand, six hundred ninety-one".