12655221 has 16 divisors (see below), whose sum is σ = 18086784. Its totient is φ = 7850304.

The previous prime is 12655219. The next prime is 12655231. The reversal of 12655221 is 12255621.

It is a happy number.

It is not a de Polignac number, because 12655221 - 2¹ = 12655219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 12655191 and 12655200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12655231) 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 15 ways as a sum of consecutive naturals, for example, 75 + ... + 5031.

It is an arithmetic number, because the mean of its divisors is an integer number (1130424).

Almost surely, 2^12655221 is an apocalyptic number.

It is an amenable number.

12655221 is a deficient number, since it is larger than the sum of its proper divisors (5431563).

12655221 is a wasteful number, since it uses less digits than its factorization.

12655221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5020.

The product of its digits is 1200, while the sum is 24.

The square root of 12655221 is about 3557.4177432514. The cubic root of 12655221 is about 233.0361220376.

The spelling of 12655221 in words is "twelve million, six hundred fifty-five thousand, two hundred twenty-one".