168991908 has 12 divisors (see below), whose sum is σ = 394314480. Its totient is φ = 56330632.

The previous prime is 168991897. The next prime is 168991937. The reversal of 168991908 is 809199861.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 7041318 + ... + 7041341.

It is an arithmetic number, because the mean of its divisors is an integer number (32859540).

Almost surely, 2^168991908 is an apocalyptic number.

It is an amenable number.

168991908 is an abundant number, since it is smaller than the sum of its proper divisors (225322572).

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

168991908 is a wasteful number, since it uses less digits than its factorization.

168991908 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14082666 (or 14082664 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 51.

The square root of 168991908 is about 12999.6887655051. The cubic root of 168991908 is about 552.8686569971.

The spelling of 168991908 in words is "one hundred sixty-eight million, nine hundred ninety-one thousand, nine hundred eight".