198631 has 4 divisors (see below), whose sum is σ = 200200. Its totient is φ = 197064.

The previous prime is 198623. The next prime is 198637. The reversal of 198631 is 136891.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 136891 = 367 ⋅373.

It is a cyclic number.

It is not a de Polignac number, because 198631 - 2³ = 198623 is a prime.

It is a super-2 number, since 2×198631² = 78908548322, which contains 22 as substring.

It is a Duffinian number.

It is a zygodrome in base 2.

It is a self number, because there is not a number n which added to its sum of digits gives 198631.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198637) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 576 + ... + 853.

It is an arithmetic number, because the mean of its divisors is an integer number (50050).

2¹⁹⁸⁶³¹ is an apocalyptic number.

198631 is a deficient number, since it is larger than the sum of its proper divisors (1569).

198631 is a wasteful number, since it uses less digits than its factorization.

198631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1568.

The product of its digits is 1296, while the sum is 28.

The square root of 198631 is about 445.6803787469. The cubic root of 198631 is about 58.3466164762.

The spelling of 198631 in words is "one hundred ninety-eight thousand, six hundred thirty-one".