13237981 has 2 divisors, whose sum is σ = 13237982. Its totient is φ = 13237980.

The previous prime is 13237979. The next prime is 13237997. The reversal of 13237981 is 18973231.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9665881 + 3572100 = 3109^2 + 1890^2 .

It is an emirp because it is prime and its reverse (18973231) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13237981 - 2¹ = 13237979 is a prime.

It is a super-2 number, since 2×13237981² = 350488281912722, which contains 22 as substring.

Together with 13237979, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13237901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6618990 + 6618991.

It is an arithmetic number, because the mean of its divisors is an integer number (6618991).

Almost surely, 2^13237981 is an apocalyptic number.

It is an amenable number.

13237981 is a deficient number, since it is larger than the sum of its proper divisors (1).

13237981 is an equidigital number, since it uses as much as digits as its factorization.

13237981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 9072, while the sum is 34.

The square root of 13237981 is about 3638.4036334634. The cubic root of 13237981 is about 236.5596039804.

The spelling of 13237981 in words is "thirteen million, two hundred thirty-seven thousand, nine hundred eighty-one".