198820 has 12 divisors (see below), whose sum is σ = 417564. Its totient is φ = 79520.

The previous prime is 198817. The next prime is 198823. The reversal of 198820 is 28891.

It is an interprime number because it is at equal distance from previous prime (198817) and next prime (198823).

It can be written as a sum of positive squares in 2 ways, for example, as 20736 + 178084 = 144^2 + 422^2 .

It is not an unprimeable number, because it can be changed into a prime (198823) 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, 4951 + ... + 4990.

It is an arithmetic number, because the mean of its divisors is an integer number (34797).

2¹⁹⁸⁸²⁰ is an apocalyptic number.

198820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

198820 is an abundant number, since it is smaller than the sum of its proper divisors (218744).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

198820 is a wasteful number, since it uses less digits than its factorization.

198820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9950 (or 9948 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 28.

The square root of 198820 is about 445.8923636933. The cubic root of 198820 is about 58.3651164665.

The spelling of 198820 in words is "one hundred ninety-eight thousand, eight hundred twenty".