13187917 has 2 divisors, whose sum is σ = 13187918. Its totient is φ = 13187916.

The previous prime is 13187897. The next prime is 13187921. The reversal of 13187917 is 71978131.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11964681 + 1223236 = 3459^2 + 1106^2 .

It is an emirp because it is prime and its reverse (71978131) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 13187917 - 2⁷ = 13187789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (13187987) 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 as a sum of consecutive naturals, namely, 6593958 + 6593959.

It is an arithmetic number, because the mean of its divisors is an integer number (6593959).

Almost surely, 2^13187917 is an apocalyptic number.

It is an amenable number.

13187917 is a deficient number, since it is larger than the sum of its proper divisors (1).

13187917 is an equidigital number, since it uses as much as digits as its factorization.

13187917 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10584, while the sum is 37.

The square root of 13187917 is about 3631.5171760574. The cubic root of 13187917 is about 236.2610166284.

The spelling of 13187917 in words is "thirteen million, one hundred eighty-seven thousand, nine hundred seventeen".