12491 has 2 divisors, whose sum is σ = 12492.
Its totient is φ = 12490.
The previous prime is 12487. The next prime is 12497. The reversal of 12491 is 19421.
It is a happy number.
12491 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 is an emirp because it is prime and its reverse (19421) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 12491 - 22 = 12487 is a prime.
It is a plaindrome in base 6 and base 13.
It is not a weakly prime, because it can be changed into another prime (12497) by changing a digit.
It is a pernicious number, because its binary representation contains a prime number (7) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6245 + 6246.
It is an arithmetic number, because the mean of its divisors is an integer number (6246).
212491 is an apocalyptic number.
12491 is a deficient number, since it is larger than the sum of its proper divisors (1).
12491 is an equidigital number, since it uses as much as digits as its factorization.
12491 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 72, while the sum is 17.
The square root of 12491 is about 111.7631424039.
The cubic root of 12491 is about 23.2023729242.
The spelling of 12491 in words is "twelve thousand, four hundred ninety-one".