199981161101 has 2 divisors, whose sum is σ = 199981161102. Its totient is φ = 199981161100.

The previous prime is 199981161097. The next prime is 199981161167. The reversal of 199981161101 is 101161189991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 190531377001 + 9449784100 = 436499^2 + 97210^2 .

It is an emirp because it is prime and its reverse (101161189991) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 101191186661 and 166681191101.

It is a cyclic number.

It is not a de Polignac number, because 199981161101 - 2² = 199981161097 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199981167101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99990580550 + 99990580551.

It is an arithmetic number, because the mean of its divisors is an integer number (99990580551).

Almost surely, 2^199981161101 is an apocalyptic number.

It is an amenable number.

199981161101 is a deficient number, since it is larger than the sum of its proper divisors (1).

199981161101 is an equidigital number, since it uses as much as digits as its factorization.

199981161101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34992, while the sum is 47.

The spelling of 199981161101 in words is "one hundred ninety-nine billion, nine hundred eighty-one million, one hundred sixty-one thousand, one hundred one".