12904221 has 16 divisors (see below), whose sum is σ = 18892800. Its totient is φ = 7769520.

The previous prime is 12904193. The next prime is 12904223. The reversal of 12904221 is 12240921.

12904221 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12904221 - 2⁵ = 12904189 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12904223) 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 15 ways as a sum of consecutive naturals, for example, 4180 + ... + 6578.

It is an arithmetic number, because the mean of its divisors is an integer number (1180800).

Almost surely, 2^12904221 is an apocalyptic number.

12904221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12904221 is a deficient number, since it is larger than the sum of its proper divisors (5988579).

12904221 is a wasteful number, since it uses less digits than its factorization.

12904221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2576.

The product of its (nonzero) digits is 288, while the sum is 21.

The square root of 12904221 is about 3592.2445629439. The cubic root of 12904221 is about 234.5545871228.

The spelling of 12904221 in words is "twelve million, nine hundred four thousand, two hundred twenty-one".