198210409 has 2 divisors, whose sum is σ = 198210410. Its totient is φ = 198210408.

The previous prime is 198210377. The next prime is 198210431. The reversal of 198210409 is 904012891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198021184 + 189225 = 14072^2 + 435^2 .

It is a cyclic number.

It is not a de Polignac number, because 198210409 - 2⁵ = 198210377 is a prime.

It is not a weakly prime, because it can be changed into another prime (198210469) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99105204 + 99105205.

It is an arithmetic number, because the mean of its divisors is an integer number (99105205).

Almost surely, 2^198210409 is an apocalyptic number.

It is an amenable number.

198210409 is a deficient number, since it is larger than the sum of its proper divisors (1).

198210409 is an equidigital number, since it uses as much as digits as its factorization.

198210409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5184, while the sum is 34.

The square root of 198210409 is about 14078.7218524978. The cubic root of 198210409 is about 583.0540538132.

The spelling of 198210409 in words is "one hundred ninety-eight million, two hundred ten thousand, four hundred nine".