12456221 has 2 divisors, whose sum is σ = 12456222. Its totient is φ = 12456220.

The previous prime is 12456217. The next prime is 12456253. The reversal of 12456221 is 12265421.

It is a happy number.

12456221 is digitally balanced in base 2, 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., 7344100 + 5112121 = 2710^2 + 2261^2 .

It is a cyclic number.

It is not a de Polignac number, because 12456221 - 2² = 12456217 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is equal to p₈₁₆₀₅₃ and since 12456221 and 816053 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12456211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6228110 + 6228111.

It is an arithmetic number, because the mean of its divisors is an integer number (6228111).

Almost surely, 2^12456221 is an apocalyptic number.

It is an amenable number.

12456221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12456221 is an equidigital number, since it uses as much as digits as its factorization.

12456221 is an evil number, because the sum of its binary digits is even.

The product of its digits is 960, while the sum is 23.

The square root of 12456221 is about 3529.3371898984. The cubic root of 12456221 is about 231.8081859355.

The spelling of 12456221 in words is "twelve million, four hundred fifty-six thousand, two hundred twenty-one".