6638668 has 6 divisors (see below), whose sum is σ = 11617676. Its totient is φ = 3319332.

The previous prime is 6638647. The next prime is 6638669. The reversal of 6638668 is 8668366.

It is not an unprimeable number, because it can be changed into a prime (6638669) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 829830 + ... + 829837.

Almost surely, 2^6638668 is an apocalyptic number.

It is an amenable number.

6638668 is a deficient number, since it is larger than the sum of its proper divisors (4979008).

6638668 is a wasteful number, since it uses less digits than its factorization.

6638668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1659671 (or 1659669 counting only the distinct ones).

The product of its digits is 248832, while the sum is 43.

The square root of 6638668 is about 2576.5612742568. The cubic root of 6638668 is about 187.9433585212.

Subtracting from 6638668 its product of digits (248832), we obtain a palindrome (6389836).

The spelling of 6638668 in words is "six million, six hundred thirty-eight thousand, six hundred sixty-eight".