8991668 has 24 divisors (see below), whose sum is σ = 18255552. Its totient is φ = 3795264.

The previous prime is 8991667. The next prime is 8991679. The reversal of 8991668 is 8661998.

It is a Smith number, since the sum of its digits (47) coincides with the sum of the digits of its prime factors.

8991668 is a strobogrammatic number because it is the same when read upside-down.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8991667) 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 7 ways as a sum of consecutive naturals, for example, 521 + ... + 4272.

It is an arithmetic number, because the mean of its divisors is an integer number (760648).

Almost surely, 2^8991668 is an apocalyptic number.

It is an amenable number.

8991668 is an abundant number, since it is smaller than the sum of its proper divisors (9263884).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8991668 is a wasteful number, since it uses less digits than its factorization.

8991668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4871 (or 4869 counting only the distinct ones).

The product of its digits is 186624, while the sum is 47.

The square root of 8991668 is about 2998.6110117853. The cubic root of 8991668 is about 207.9441726405.

The spelling of 8991668 in words is "eight million, nine hundred ninety-one thousand, six hundred sixty-eight".