12817 has 4 divisors (see below), whose sum is σ = 14656. Its totient is φ = 10980.

The previous prime is 12809. The next prime is 12821. The reversal of 12817 is 71821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 12817 - 2³ = 12809 is a prime.

It is a Duffinian number.

It is a plaindrome in base 13.

It is a nialpdrome in base 16.

It is a junction number, because it is equal to n+sod(n) for n = 12794 and 12803.

It is not an unprimeable number, because it can be changed into a prime (12517) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 909 + ... + 922.

It is an arithmetic number, because the mean of its divisors is an integer number (3664).

2¹²⁸¹⁷ is an apocalyptic number.

It is an amenable number.

12817 is a deficient number, since it is larger than the sum of its proper divisors (1839).

12817 is an equidigital number, since it uses as much as digits as its factorization.

12817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1838.

The product of its digits is 112, while the sum is 19.

The square root of 12817 is about 113.2121901564. The cubic root of 12817 is about 23.4024932206.

The spelling of 12817 in words is "twelve thousand, eight hundred seventeen".