199988771 has 2 divisors, whose sum is σ = 199988772. Its totient is φ = 199988770.

The previous prime is 199988759. The next prime is 199988773. The reversal of 199988771 is 177889991.

It is a strong prime.

It is an emirp because it is prime and its reverse (177889991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199988771 - 2¹⁰ = 199987747 is a prime.

Together with 199988773, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 199988771.

It is not a weakly prime, because it can be changed into another prime (199988773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99994385 + 99994386.

It is an arithmetic number, because the mean of its divisors is an integer number (99994386).

Almost surely, 2^199988771 is an apocalyptic number.

199988771 is a deficient number, since it is larger than the sum of its proper divisors (1).

199988771 is an equidigital number, since it uses as much as digits as its factorization.

199988771 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 59.

The square root of 199988771 is about 14141.7386130560. The cubic root of 199988771 is about 584.7926028393.

The spelling of 199988771 in words is "one hundred ninety-nine million, nine hundred eighty-eight thousand, seven hundred seventy-one".