12856021 has 2 divisors, whose sum is σ = 12856022. Its totient is φ = 12856020.

The previous prime is 12856013. The next prime is 12856033. The reversal of 12856021 is 12065821.

12856021 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8059921 + 4796100 = 2839^2 + 2190^2 .

It is a cyclic number.

It is not a de Polignac number, because 12856021 - 2³ = 12856013 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12856091) 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, 6428010 + 6428011.

It is an arithmetic number, because the mean of its divisors is an integer number (6428011).

Almost surely, 2^12856021 is an apocalyptic number.

It is an amenable number.

12856021 is a deficient number, since it is larger than the sum of its proper divisors (1).

12856021 is an equidigital number, since it uses as much as digits as its factorization.

12856021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 12856021 is about 3585.5293890861. The cubic root of 12856021 is about 234.2621857303.

The spelling of 12856021 in words is "twelve million, eight hundred fifty-six thousand, twenty-one".