198781133 has 2 divisors, whose sum is σ = 198781134. Its totient is φ = 198781132.

The previous prime is 198781087. The next prime is 198781147. The reversal of 198781133 is 331187891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 195384484 + 3396649 = 13978^2 + 1843^2 .

It is a cyclic number.

It is not a de Polignac number, because 198781133 - 2¹² = 198777037 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (198781183) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99390566 + 99390567.

It is an arithmetic number, because the mean of its divisors is an integer number (99390567).

Almost surely, 2^198781133 is an apocalyptic number.

It is an amenable number.

198781133 is a deficient number, since it is larger than the sum of its proper divisors (1).

198781133 is an equidigital number, since it uses as much as digits as its factorization.

198781133 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 36288, while the sum is 41.

The square root of 198781133 is about 14098.9763103567. The cubic root of 198781133 is about 583.6131298464.

The spelling of 198781133 in words is "one hundred ninety-eight million, seven hundred eighty-one thousand, one hundred thirty-three".