6649221 has 32 divisors (see below), whose sum is σ = 9953280. Its totient is φ = 3931200.

The previous prime is 6649199. The next prime is 6649229. The reversal of 6649221 is 1229466.

It is not a de Polignac number, because 6649221 - 2⁵ = 6649189 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6649229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93616 + ... + 93686.

It is an arithmetic number, because the mean of its divisors is an integer number (311040).

Almost surely, 2^6649221 is an apocalyptic number.

It is an amenable number.

6649221 is a deficient number, since it is larger than the sum of its proper divisors (3304059).

6649221 is a wasteful number, since it uses less digits than its factorization.

6649221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177.

The product of its digits is 5184, while the sum is 30.

The square root of 6649221 is about 2578.6083456004. The cubic root of 6649221 is about 188.0428923561.

The spelling of 6649221 in words is "six million, six hundred forty-nine thousand, two hundred twenty-one".