198179857 has 2 divisors, whose sum is σ = 198179858. Its totient is φ = 198179856.

The previous prime is 198179809. The next prime is 198179887. The reversal of 198179857 is 758971891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 194630401 + 3549456 = 13951^2 + 1884^2 .

It is a cyclic number.

It is not a de Polignac number, because 198179857 - 2¹⁹ = 197655569 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 198179798 and 198179807.

It is not a weakly prime, because it can be changed into another prime (198179887) 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, 99089928 + 99089929.

It is an arithmetic number, because the mean of its divisors is an integer number (99089929).

Almost surely, 2^198179857 is an apocalyptic number.

It is an amenable number.

198179857 is a deficient number, since it is larger than the sum of its proper divisors (1).

198179857 is an equidigital number, since it uses as much as digits as its factorization.

198179857 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1270080, while the sum is 55.

The square root of 198179857 is about 14077.6367690035. The cubic root of 198179857 is about 583.0240951061.

The spelling of 198179857 in words is "one hundred ninety-eight million, one hundred seventy-nine thousand, eight hundred fifty-seven".