198590857 has 2 divisors, whose sum is σ = 198590858. Its totient is φ = 198590856.

The previous prime is 198590851. The next prime is 198590897. The reversal of 198590857 is 758095891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182358016 + 16232841 = 13504^2 + 4029^2 .

It is a cyclic number.

It is not a de Polignac number, because 198590857 - 2¹¹ = 198588809 is a prime.

It is not a weakly prime, because it can be changed into another prime (198590851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99295428 + 99295429.

It is an arithmetic number, because the mean of its divisors is an integer number (99295429).

Almost surely, 2^198590857 is an apocalyptic number.

It is an amenable number.

198590857 is a deficient number, since it is larger than the sum of its proper divisors (1).

198590857 is an equidigital number, since it uses as much as digits as its factorization.

198590857 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 907200, while the sum is 52.

The square root of 198590857 is about 14092.2268290004. The cubic root of 198590857 is about 583.4268562614.

The spelling of 198590857 in words is "one hundred ninety-eight million, five hundred ninety thousand, eight hundred fifty-seven".