198865 has 8 divisors (see below), whose sum is σ = 246528. Its totient is φ = 153840.

The previous prime is 198859. The next prime is 198899. The reversal of 198865 is 568891.

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

It is not a de Polignac number, because 198865 - 2⁵ = 198833 is a prime.

It is a Duffinian number.

198865 is a lucky 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, 487 + ... + 796.

It is an arithmetic number, because the mean of its divisors is an integer number (30816).

2¹⁹⁸⁸⁶⁵ is an apocalyptic number.

It is an amenable number.

198865 is a deficient number, since it is larger than the sum of its proper divisors (47663).

198865 is a wasteful number, since it uses less digits than its factorization.

198865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1319.

The product of its digits is 17280, while the sum is 37.

The square root of 198865 is about 445.9428214469. The cubic root of 198865 is about 58.3695194980.

It can be divided in two parts, 19886 and 5, that added together give a palindrome (19891).

The spelling of 198865 in words is "one hundred ninety-eight thousand, eight hundred sixty-five".