199961903171 has 2 divisors, whose sum is σ = 199961903172. Its totient is φ = 199961903170.

The previous prime is 199961903161. The next prime is 199961903257. The reversal of 199961903171 is 171309169991.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199961903171 is a prime.

It is not a weakly prime, because it can be changed into another prime (199961903161) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99980951585 + 99980951586.

It is an arithmetic number, because the mean of its divisors is an integer number (99980951586).

Almost surely, 2^199961903171 is an apocalyptic number.

199961903171 is a deficient number, since it is larger than the sum of its proper divisors (1).

199961903171 is an equidigital number, since it uses as much as digits as its factorization.

199961903171 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 826686, while the sum is 56.

The spelling of 199961903171 in words is "one hundred ninety-nine billion, nine hundred sixty-one million, nine hundred three thousand, one hundred seventy-one".