198603891281 has 2 divisors, whose sum is σ = 198603891282. Its totient is φ = 198603891280.

The previous prime is 198603891251. The next prime is 198603891293. The reversal of 198603891281 is 182198306891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 198332169025 + 271722256 = 445345^2 + 16484^2 .

It is a cyclic number.

It is not a de Polignac number, because 198603891281 - 2⁶ = 198603891217 is a prime.

It is a super-2 number, since 2×198603891281² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (198603891221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99301945640 + 99301945641.

It is an arithmetic number, because the mean of its divisors is an integer number (99301945641).

Almost surely, 2^198603891281 is an apocalyptic number.

It is an amenable number.

198603891281 is a deficient number, since it is larger than the sum of its proper divisors (1).

198603891281 is an equidigital number, since it uses as much as digits as its factorization.

198603891281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1492992, while the sum is 56.

The spelling of 198603891281 in words is "one hundred ninety-eight billion, six hundred three million, eight hundred ninety-one thousand, two hundred eighty-one".