197998189 has 2 divisors, whose sum is σ = 197998190. Its totient is φ = 197998188.

The previous prime is 197998181. The next prime is 197998217. The reversal of 197998189 is 981899791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 197262025 + 736164 = 14045^2 + 858^2 .

It is a cyclic number.

It is not a de Polignac number, because 197998189 - 2³ = 197998181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (197998181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 98999094 + 98999095.

It is an arithmetic number, because the mean of its divisors is an integer number (98999095).

Almost surely, 2^197998189 is an apocalyptic number.

It is an amenable number.

197998189 is a deficient number, since it is larger than the sum of its proper divisors (1).

197998189 is an equidigital number, since it uses as much as digits as its factorization.

197998189 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2939328, while the sum is 61.

The square root of 197998189 is about 14071.1829282403. The cubic root of 197998189 is about 582.8458913212.

The spelling of 197998189 in words is "one hundred ninety-seven million, nine hundred ninety-eight thousand, one hundred eighty-nine".