168133681 has 8 divisors (see below), whose sum is σ = 170692704. Its totient is φ = 165587520.

The previous prime is 168133663. The next prime is 168133709. The reversal of 168133681 is 186331861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-168133681 is a prime.

It is a super-2 number, since 2×168133681² = 56537869373219522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 168133681.

It is not an unprimeable number, because it can be changed into a prime (168133601) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24966 + ... + 30976.

It is an arithmetic number, because the mean of its divisors is an integer number (21336588).

Almost surely, 2^168133681 is an apocalyptic number.

It is an amenable number.

168133681 is a deficient number, since it is larger than the sum of its proper divisors (2559023).

168133681 is an equidigital number, since it uses as much as digits as its factorization.

168133681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6431.

The product of its digits is 20736, while the sum is 37.

The square root of 168133681 is about 12966.6372279015. The cubic root of 168133681 is about 551.9311519275.

The spelling of 168133681 in words is "one hundred sixty-eight million, one hundred thirty-three thousand, six hundred eighty-one".