198123 has 4 divisors (see below), whose sum is σ = 264168. Its totient is φ = 132080.

The previous prime is 198109. The next prime is 198127. The reversal of 198123 is 321891.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 198123 - 2⁵ = 198091 is a prime.

It is a super-3 number, since 3×198123³ = 23330601793460601, which contains 333 as substring.

It is a D-number.

198123 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 198093 and 198102.

It is not an unprimeable number, because it can be changed into a prime (198127) 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, 33018 + ... + 33023.

It is an arithmetic number, because the mean of its divisors is an integer number (66042).

2¹⁹⁸¹²³ is an apocalyptic number.

198123 is a deficient number, since it is larger than the sum of its proper divisors (66045).

198123 is an equidigital number, since it uses as much as digits as its factorization.

198123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66044.

The product of its digits is 432, while the sum is 24.

The square root of 198123 is about 445.1100987396. The cubic root of 198123 is about 58.2968334021.

The spelling of 198123 in words is "one hundred ninety-eight thousand, one hundred twenty-three".