199915571171 has 2 divisors, whose sum is σ = 199915571172. Its totient is φ = 199915571170.

The previous prime is 199915571161. The next prime is 199915571203. The reversal of 199915571171 is 171175519991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 199915571171 - 2²² = 199911376867 is a prime.

It is a super-2 number, since 2×199915571171² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (199915571131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99957785585 + 99957785586.

It is an arithmetic number, because the mean of its divisors is an integer number (99957785586).

Almost surely, 2^199915571171 is an apocalyptic number.

199915571171 is a deficient number, since it is larger than the sum of its proper divisors (1).

199915571171 is an equidigital number, since it uses as much as digits as its factorization.

199915571171 is an evil number, because the sum of its binary digits is even.

The product of its digits is 893025, while the sum is 56.

The spelling of 199915571171 in words is "one hundred ninety-nine billion, nine hundred fifteen million, five hundred seventy-one thousand, one hundred seventy-one".