198489921 has 16 divisors (see below), whose sum is σ = 302674944. Its totient is φ = 113342544.

The previous prime is 198489901. The next prime is 198489997. The reversal of 198489921 is 129984891.

It is not a de Polignac number, because 198489921 - 2⁶ = 198489857 is a prime.

It is a super-3 number, since 3×198489921³ (a number of 26 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (198489901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40236 + ... + 44898.

It is an arithmetic number, because the mean of its divisors is an integer number (18917184).

Almost surely, 2^198489921 is an apocalyptic number.

It is an amenable number.

198489921 is a deficient number, since it is larger than the sum of its proper divisors (104185023).

198489921 is a wasteful number, since it uses less digits than its factorization.

198489921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6700.

The product of its digits is 373248, while the sum is 51.

The square root of 198489921 is about 14088.6451087392. The cubic root of 198489921 is about 583.3279951258.

The spelling of 198489921 in words is "one hundred ninety-eight million, four hundred eighty-nine thousand, nine hundred twenty-one".