12820889 has 2 divisors, whose sum is σ = 12820890. Its totient is φ = 12820888.

The previous prime is 12820883. The next prime is 12820891. The reversal of 12820889 is 98802821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12816400 + 4489 = 3580^2 + 67^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12820889 is a prime.

Together with 12820891, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (12820883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6410444 + 6410445.

It is an arithmetic number, because the mean of its divisors is an integer number (6410445).

Almost surely, 2^12820889 is an apocalyptic number.

It is an amenable number.

12820889 is a deficient number, since it is larger than the sum of its proper divisors (1).

12820889 is an equidigital number, since it uses as much as digits as its factorization.

12820889 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18432, while the sum is 38.

The square root of 12820889 is about 3580.6269004184. The cubic root of 12820889 is about 234.0485994949.

The spelling of 12820889 in words is "twelve million, eight hundred twenty thousand, eight hundred eighty-nine".