12288221 has 4 divisors (see below), whose sum is σ = 13405344. Its totient is φ = 11171100.

The previous prime is 12288173. The next prime is 12288259.

12288221 is nontrivially palindromic in base 10.

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 not a de Polignac number, because 12288221 - 2¹⁴ = 12271837 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 (12288281) 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, 558545 + ... + 558566.

It is an arithmetic number, because the mean of its divisors is an integer number (3351336).

Almost surely, 2^12288221 is an apocalyptic number.

12288221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12288221 is a deficient number, since it is larger than the sum of its proper divisors (1117123).

12288221 is a wasteful number, since it uses less digits than its factorization.

12288221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1117122.

The product of its digits is 1024, while the sum is 26.

The square root of 12288221 is about 3505.4558904656. The cubic root of 12288221 is about 230.7613146487.

It can be divided in two parts, 1228 and 8221, that added together give a palindrome (9449).

The spelling of 12288221 in words is "twelve million, two hundred eighty-eight thousand, two hundred twenty-one".