198880109 has 2 divisors, whose sum is σ = 198880110. Its totient is φ = 198880108.

The previous prime is 198880079. The next prime is 198880111. The reversal of 198880109 is 901088891.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196981225 + 1898884 = 14035^2 + 1378^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-198880109 is a prime.

It is a Sophie Germain prime.

Together with 198880111, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 198880109.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198880309) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99440054 + 99440055.

It is an arithmetic number, because the mean of its divisors is an integer number (99440055).

Almost surely, 2^198880109 is an apocalyptic number.

It is an amenable number.

198880109 is a deficient number, since it is larger than the sum of its proper divisors (1).

198880109 is an equidigital number, since it uses as much as digits as its factorization.

198880109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 41472, while the sum is 44.

The square root of 198880109 is about 14102.4859156108. The cubic root of 198880109 is about 583.7099769126.

The spelling of 198880109 in words is "one hundred ninety-eight million, eight hundred eighty thousand, one hundred nine".