198985 has 8 divisors (see below), whose sum is σ = 252936.
Its totient is φ = 149760.
The previous prime is 198977. The next prime is 198997. The reversal of 198985 is 589891.
It can be written as a sum of positive squares in 4 ways, for example, as 53824 + 145161 = 232^2 + 381^2
It is a sphenic number, since it is the product of 3 distinct primes.
It is not a de Polignac number, because 198985 - 23 = 198977 is a prime.
It is a Duffinian number.
It is a congruent number.
It is an unprimeable 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 7 ways as a sum of consecutive naturals, for example, 1086 + ... + 1255.
It is an arithmetic number, because the mean of its divisors is an integer number (31617).
2198985 is an apocalyptic number.
It is an amenable number.
198985 is a deficient number, since it is larger than the sum of its proper divisors (53951).
198985 is a wasteful number, since it uses less digits than its factorization.
198985 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 2363.
The product of its digits is 25920, while the sum is 40.
The square root of 198985 is about 446.0773475531.
The cubic root of 198985 is about 58.3812576687.
The spelling of 198985 in words is "one hundred ninety-eight thousand, nine hundred eighty-five".