6555221 has 8 divisors (see below), whose sum is σ = 6757344. Its totient is φ = 6355440.

The previous prime is 6555173. The next prime is 6555223. The reversal of 6555221 is 1225556.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 6555221 - 2¹⁴ = 6538837 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a nialpdrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6555223) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6266 + ... + 7236.

It is an arithmetic number, because the mean of its divisors is an integer number (844668).

Almost surely, 2^6555221 is an apocalyptic number.

It is an amenable number.

6555221 is a deficient number, since it is larger than the sum of its proper divisors (202123).

6555221 is a wasteful number, since it uses less digits than its factorization.

6555221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1171.

The product of its digits is 3000, while the sum is 26.

The square root of 6555221 is about 2560.3165819875. The cubic root of 6555221 is about 187.1525631168.

It can be divided in two parts, 6555 and 221, that added together give a palindrome (6776).

The spelling of 6555221 in words is "six million, five hundred fifty-five thousand, two hundred twenty-one".