6628181 has 24 divisors (see below), whose sum is σ = 8351640. Its totient is φ = 5225472.

The previous prime is 6628177. The next prime is 6628189. The reversal of 6628181 is 1818266.

It can be written as a sum of positive squares in 4 ways, for example, as 2592100 + 4036081 = 1610^2 + 2009^2 .

It is not a de Polignac number, because 6628181 - 2² = 6628177 is a prime.

It is a super-2 number, since 2×6628181² = 87865566737522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6628189) 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 23 ways as a sum of consecutive naturals, for example, 60755 + ... + 60863.

It is an arithmetic number, because the mean of its divisors is an integer number (347985).

Almost surely, 2^6628181 is an apocalyptic number.

It is an amenable number.

6628181 is a deficient number, since it is larger than the sum of its proper divisors (1723459).

6628181 is a wasteful number, since it uses less digits than its factorization.

6628181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 206 counting only the distinct ones).

The product of its digits is 4608, while the sum is 32.

The square root of 6628181 is about 2574.5253931550. The cubic root of 6628181 is about 187.8443426371.

The spelling of 6628181 in words is "six million, six hundred twenty-eight thousand, one hundred eighty-one".