12867221 has 4 divisors (see below), whose sum is σ = 12941772. Its totient is φ = 12792672.

The previous prime is 12867209. The next prime is 12867223. The reversal of 12867221 is 12276821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5244100 + 7623121 = 2290^2 + 2761^2 .

It is a cyclic number.

It is not a de Polignac number, because 12867221 - 2¹⁰ = 12866197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12867223) 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 in 3 ways as a sum of consecutive naturals, for example, 37016 + ... + 37361.

It is an arithmetic number, because the mean of its divisors is an integer number (3235443).

Almost surely, 2^12867221 is an apocalyptic number.

It is an amenable number.

12867221 is a deficient number, since it is larger than the sum of its proper divisors (74551).

12867221 is an equidigital number, since it uses as much as digits as its factorization.

12867221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74550.

The product of its digits is 2688, while the sum is 29.

The square root of 12867221 is about 3587.0908825955. The cubic root of 12867221 is about 234.3301947181.

The spelling of 12867221 in words is "twelve million, eight hundred sixty-seven thousand, two hundred twenty-one".