198491177 has 2 divisors, whose sum is σ = 198491178. Its totient is φ = 198491176.

The previous prime is 198491149. The next prime is 198491179. The reversal of 198491177 is 771194891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 160680976 + 37810201 = 12676^2 + 6149^2 .

It is a cyclic number.

It is not a de Polignac number, because 198491177 - 2⁶ = 198491113 is a prime.

Together with 198491179, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (198491179) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99245588 + 99245589.

It is an arithmetic number, because the mean of its divisors is an integer number (99245589).

Almost surely, 2^198491177 is an apocalyptic number.

It is an amenable number.

198491177 is a deficient number, since it is larger than the sum of its proper divisors (1).

198491177 is an equidigital number, since it uses as much as digits as its factorization.

198491177 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 127008, while the sum is 47.

The square root of 198491177 is about 14088.6896835724. The cubic root of 198491177 is about 583.3292255130.

The spelling of 198491177 in words is "one hundred ninety-eight million, four hundred ninety-one thousand, one hundred seventy-seven".