198659819 has 2 divisors, whose sum is σ = 198659820. Its totient is φ = 198659818.

The previous prime is 198659789. The next prime is 198659827. The reversal of 198659819 is 918956891.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 198659819 - 2²⁰ = 197611243 is a prime.

It is a super-2 number, since 2×198659819² = 78931447370225522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (198659849) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99329909 + 99329910.

It is an arithmetic number, because the mean of its divisors is an integer number (99329910).

Almost surely, 2^198659819 is an apocalyptic number.

198659819 is a deficient number, since it is larger than the sum of its proper divisors (1).

198659819 is an equidigital number, since it uses as much as digits as its factorization.

198659819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1399680, while the sum is 56.

The square root of 198659819 is about 14094.6734265112. The cubic root of 198659819 is about 583.4943814019.

The spelling of 198659819 in words is "one hundred ninety-eight million, six hundred fifty-nine thousand, eight hundred nineteen".