12991241 has 4 divisors (see below), whose sum is σ = 13137300. Its totient is φ = 12845184.

The previous prime is 12991229. The next prime is 12991249. The reversal of 12991241 is 14219921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14219921 = 79 ⋅179999.

It can be written as a sum of positive squares in 2 ways, for example, as 3225616 + 9765625 = 1796^2 + 3125^2 .

It is a cyclic number.

It is not a de Polignac number, because 12991241 - 2⁶ = 12991177 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (12991249) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72896 + ... + 73073.

It is an arithmetic number, because the mean of its divisors is an integer number (3284325).

Almost surely, 2^12991241 is an apocalyptic number.

It is an amenable number.

12991241 is a deficient number, since it is larger than the sum of its proper divisors (146059).

12991241 is an equidigital number, since it uses as much as digits as its factorization.

12991241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 146058.

The product of its digits is 1296, while the sum is 29.

The square root of 12991241 is about 3604.3364160411. The cubic root of 12991241 is about 235.0806483419.

The spelling of 12991241 in words is "twelve million, nine hundred ninety-one thousand, two hundred forty-one".