198866 has 8 divisors (see below), whose sum is σ = 315900. Its totient is φ = 93568.

The previous prime is 198859. The next prime is 198899. The reversal of 198866 is 668891.

It can be written as a sum of positive squares in 2 ways, for example, as 198025 + 841 = 445^2 + 29^2 .

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

It is an unprimeable number.

198866 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 3 ways as a sum of consecutive naturals, for example, 2891 + ... + 2958.

2¹⁹⁸⁸⁶⁶ is an apocalyptic number.

198866 is a deficient number, since it is larger than the sum of its proper divisors (117034).

198866 is a wasteful number, since it uses less digits than its factorization.

198866 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5868.

The product of its digits is 20736, while the sum is 38.

The square root of 198866 is about 445.9439426654. The cubic root of 198866 is about 58.3696173356.

It can be divided in two parts, 19886 and 6, that multiplied together give a triangular number (119316 = T₄₈₈).

The spelling of 198866 in words is "one hundred ninety-eight thousand, eight hundred sixty-six".