198138 has 8 divisors (see below), whose sum is σ = 396288. Its totient is φ = 66044.

The previous prime is 198127. The next prime is 198139. The reversal of 198138 is 831891.

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

198138 is an admirable number.

It is a super-3 number, since 3×198138³ = 23335901312292216, which contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (198139) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16506 + ... + 16517.

It is an arithmetic number, because the mean of its divisors is an integer number (49536).

2¹⁹⁸¹³⁸ is an apocalyptic number.

198138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

198138 is a wasteful number, since it uses less digits than its factorization.

198138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33028.

The product of its digits is 1728, while the sum is 30.

The square root of 198138 is about 445.1269481844. The cubic root of 198138 is about 58.2983045933.

The spelling of 198138 in words is "one hundred ninety-eight thousand, one hundred thirty-eight".