12109817 has 2 divisors, whose sum is σ = 12109818. Its totient is φ = 12109816.

The previous prime is 12109697. The next prime is 12109843. The reversal of 12109817 is 71890121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7513081 + 4596736 = 2741^2 + 2144^2 .

It is an emirp because it is prime and its reverse (71890121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12109817 - 2²⁰ = 11061241 is a prime.

It is a super-4 number, since 4×12109817⁴ (a number of 29 digits) contains 4444 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12109817.

It is not a weakly prime, because it can be changed into another prime (12109847) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6054908 + 6054909.

It is an arithmetic number, because the mean of its divisors is an integer number (6054909).

Almost surely, 2^12109817 is an apocalyptic number.

It is an amenable number.

12109817 is a deficient number, since it is larger than the sum of its proper divisors (1).

12109817 is an equidigital number, since it uses as much as digits as its factorization.

12109817 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1008, while the sum is 29.

The square root of 12109817 is about 3479.9162346240. The cubic root of 12109817 is about 229.6391126757.

Adding to 12109817 its reverse (71890121), we get a palindrome (83999938).

The spelling of 12109817 in words is "twelve million, one hundred nine thousand, eight hundred seventeen".