12821117 has 2 divisors, whose sum is σ = 12821118. Its totient is φ = 12821116.

The previous prime is 12821087. The next prime is 12821119. The reversal of 12821117 is 71112821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 11519236 + 1301881 = 3394^2 + 1141^2 .

It is a cyclic number.

It is not a de Polignac number, because 12821117 - 2¹⁴ = 12804733 is a prime.

It is a super-2 number, since 2×12821117² = 328762082255378, which contains 22 as substring.

Together with 12821119, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 12821092 and 12821101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12821119) 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, 6410558 + 6410559.

It is an arithmetic number, because the mean of its divisors is an integer number (6410559).

Almost surely, 2^12821117 is an apocalyptic number.

It is an amenable number.

12821117 is a deficient number, since it is larger than the sum of its proper divisors (1).

12821117 is an equidigital number, since it uses as much as digits as its factorization.

12821117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 224, while the sum is 23.

The square root of 12821117 is about 3580.6587382771. The cubic root of 12821117 is about 234.0499868860.

Adding to 12821117 its reverse (71112821), we get a palindrome (83933938).

The spelling of 12821117 in words is "twelve million, eight hundred twenty-one thousand, one hundred seventeen".