12879221 has 2 divisors, whose sum is σ = 12879222. Its totient is φ = 12879220.

The previous prime is 12879199. The next prime is 12879239. The reversal of 12879221 is 12297821.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12780625 + 98596 = 3575^2 + 314^2 .

It is an emirp because it is prime and its reverse (12297821) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12879221 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12879121) 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, 6439610 + 6439611.

It is an arithmetic number, because the mean of its divisors is an integer number (6439611).

Almost surely, 2^12879221 is an apocalyptic number.

It is an amenable number.

12879221 is a deficient number, since it is larger than the sum of its proper divisors (1).

12879221 is an equidigital number, since it uses as much as digits as its factorization.

12879221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 32.

The square root of 12879221 is about 3588.7631574123. The cubic root of 12879221 is about 234.4030177113.

The spelling of 12879221 in words is "twelve million, eight hundred seventy-nine thousand, two hundred twenty-one".