168365681 has 16 divisors (see below), whose sum is σ = 197849088. Its totient is φ = 141675600.

The previous prime is 168365663. The next prime is 168365693. The reversal of 168365681 is 186563861.

It is not a de Polignac number, because 168365681 - 2¹⁰ = 168364657 is a prime.

It is a super-2 number, since 2×168365681² = 56694005077187522, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (168365621) 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 15 ways as a sum of consecutive naturals, for example, 2891 + ... + 18576.

It is an arithmetic number, because the mean of its divisors is an integer number (12365568).

Almost surely, 2^168365681 is an apocalyptic number.

168365681 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

168365681 is a deficient number, since it is larger than the sum of its proper divisors (29483407).

168365681 is a wasteful number, since it uses less digits than its factorization.

168365681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21532.

The product of its digits is 207360, while the sum is 44.

The square root of 168365681 is about 12975.5801797068. The cubic root of 168365681 is about 552.1848967963.

The spelling of 168365681 in words is "one hundred sixty-eight million, three hundred sixty-five thousand, six hundred eighty-one".