198663 has 4 divisors (see below), whose sum is σ = 264888. Its totient is φ = 132440.

The previous prime is 198659. The next prime is 198673. The reversal of 198663 is 366891.

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 198663 - 2² = 198659 is a prime.

It is a D-number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198613) 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, 33108 + ... + 33113.

It is an arithmetic number, because the mean of its divisors is an integer number (66222).

2¹⁹⁸⁶⁶³ is an apocalyptic number.

198663 is a deficient number, since it is larger than the sum of its proper divisors (66225).

198663 is an equidigital number, since it uses as much as digits as its factorization.

198663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66224.

The product of its digits is 7776, while the sum is 33.

The square root of 198663 is about 445.7162774681. The cubic root of 198663 is about 58.3497495747.

It can be divided in two parts, 198 and 663, that added together give a triangular number (861 = T₄₁).

The spelling of 198663 in words is "one hundred ninety-eight thousand, six hundred sixty-three".