12856321 has 2 divisors, whose sum is σ = 12856322. Its totient is φ = 12856320.

The previous prime is 12856273. The next prime is 12856339. The reversal of 12856321 is 12365821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12852225 + 4096 = 3585^2 + 64^2 .

It is a cyclic number.

It is not a de Polignac number, because 12856321 - 2⁹ = 12855809 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 12856321.

It is not a weakly prime, because it can be changed into another prime (12856021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6428160 + 6428161.

It is an arithmetic number, because the mean of its divisors is an integer number (6428161).

Almost surely, 2^12856321 is an apocalyptic number.

It is an amenable number.

12856321 is a deficient number, since it is larger than the sum of its proper divisors (1).

12856321 is an equidigital number, since it uses as much as digits as its factorization.

12856321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2880, while the sum is 28.

The square root of 12856321 is about 3585.5712236686. The cubic root of 12856321 is about 234.2640079143.

The spelling of 12856321 in words is "twelve million, eight hundred fifty-six thousand, three hundred twenty-one".