12672221 has 4 divisors (see below), whose sum is σ = 13339200. Its totient is φ = 12005244.

The previous prime is 12672181. The next prime is 12672223. The reversal of 12672221 is 12227621.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12672221 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12672223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 333461 + ... + 333498.

It is an arithmetic number, because the mean of its divisors is an integer number (3334800).

Almost surely, 2^12672221 is an apocalyptic number.

It is an amenable number.

12672221 is a deficient number, since it is larger than the sum of its proper divisors (666979).

12672221 is an equidigital number, since it uses as much as digits as its factorization.

12672221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 666978.

The product of its digits is 672, while the sum is 23.

The square root of 12672221 is about 3559.8063149559. The cubic root of 12672221 is about 233.1404226393.

Adding to 12672221 its reverse (12227621), we get a palindrome (24899842).

The spelling of 12672221 in words is "twelve million, six hundred seventy-two thousand, two hundred twenty-one".