168138 has 12 divisors (see below), whose sum is σ = 364338. Its totient is φ = 56040.

The previous prime is 168127. The next prime is 168143. The reversal of 168138 is 831861.

168138 is nontrivially palindromic in base 15.

It can be written as a sum of positive squares in only one way, i.e., 154449 + 13689 = 393^2 + 117^2 .

It is an unprimeable number.

168138 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4653 + ... + 4688.

2¹⁶⁸¹³⁸ is an apocalyptic number.

168138 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

168138 is an abundant number, since it is smaller than the sum of its proper divisors (196200).

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

168138 is a wasteful number, since it uses less digits than its factorization.

168138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9349 (or 9346 counting only the distinct ones).

The product of its digits is 1152, while the sum is 27.

The square root of 168138 is about 410.0463388448. The cubic root of 168138 is about 55.1935877870.

Adding to 168138 its reverse (831861), we get a palindrome (999999).

The spelling of 168138 in words is "one hundred sixty-eight thousand, one hundred thirty-eight".