168643813 has 8 divisors (see below), whose sum is σ = 187475456. Its totient is φ = 150649200.

The previous prime is 168643789. The next prime is 168643823. The reversal of 168643813 is 318346861.

It is a happy number.

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

It is a de Polignac number, because none of the positive numbers 2^k-168643813 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (168643823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 208833 + ... + 209638.

It is an arithmetic number, because the mean of its divisors is an integer number (23434432).

Almost surely, 2^168643813 is an apocalyptic number.

168643813 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

168643813 is a deficient number, since it is larger than the sum of its proper divisors (18831643).

168643813 is a wasteful number, since it uses less digits than its factorization.

168643813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 418515.

The product of its digits is 82944, while the sum is 40.

The square root of 168643813 is about 12986.2932740640. The cubic root of 168643813 is about 552.4887904744.

The spelling of 168643813 in words is "one hundred sixty-eight million, six hundred forty-three thousand, eight hundred thirteen".