199999990222181 has 2 divisors, whose sum is σ = 199999990222182. Its totient is φ = 199999990222180.

The previous prime is 199999990222171. The next prime is 199999990222199. The reversal of 199999990222181 is 181222099999991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 199088318537956 + 911671684225 = 14109866^2 + 954815^2 .

It is a cyclic number.

It is not a de Polignac number, because 199999990222181 - 2¹⁸ = 199999989960037 is a prime.

It is a super-2 number, since 2×199999990222181² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 199999990222096 and 199999990222105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199999990222121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99999995111090 + 99999995111091.

It is an arithmetic number, because the mean of its divisors is an integer number (99999995111091).

Almost surely, 2^{199999990222181} is an apocalyptic number.

It is an amenable number.

199999990222181 is a deficient number, since it is larger than the sum of its proper divisors (1).

199999990222181 is an equidigital number, since it uses as much as digits as its factorization.

199999990222181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 306110016, while the sum is 80.

The spelling of 199999990222181 in words is "one hundred ninety-nine trillion, nine hundred ninety-nine billion, nine hundred ninety million, two hundred twenty-two thousand, one hundred eighty-one".