198163989 has 30 divisors (see below), whose sum is σ = 306687810. Its totient is φ = 127509984.

The previous prime is 198163969. The next prime is 198164003. The reversal of 198163989 is 989361891.

It can be written as a sum of positive squares in 3 ways, for example, as 67519089 + 130644900 = 8217^2 + 11430^2 .

It is not a de Polignac number, because 198163989 - 2²⁴ = 181386773 is a prime.

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (198163969) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 66667 + ... + 69575.

It is an arithmetic number, because the mean of its divisors is an integer number (10222927).

Almost surely, 2^198163989 is an apocalyptic number.

It is an amenable number.

198163989 is a deficient number, since it is larger than the sum of its proper divisors (108523821).

198163989 is an equidigital number, since it uses as much as digits as its factorization.

198163989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2979 (or 2941 counting only the distinct ones).

The product of its digits is 839808, while the sum is 54.

The square root of 198163989 is about 14077.0731688089. The cubic root of 198163989 is about 583.0085340338.

The spelling of 198163989 in words is "one hundred ninety-eight million, one hundred sixty-three thousand, nine hundred eighty-nine".