199991069 has 2 divisors, whose sum is σ = 199991070. Its totient is φ = 199991068.

The previous prime is 199991059. The next prime is 199991087. The reversal of 199991069 is 960199991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 138180025 + 61811044 = 11755^2 + 7862^2 .

It is an emirp because it is prime and its reverse (960199991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 199991069 - 2⁴ = 199991053 is a prime.

It is a super-2 number, since 2×199991069² = 79992855359525522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 199991069.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199991059) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99995534 + 99995535.

It is an arithmetic number, because the mean of its divisors is an integer number (99995535).

Almost surely, 2^199991069 is an apocalyptic number.

It is an amenable number.

199991069 is a deficient number, since it is larger than the sum of its proper divisors (1).

199991069 is an equidigital number, since it uses as much as digits as its factorization.

199991069 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 354294, while the sum is 53.

The square root of 199991069 is about 14141.8198616727. The cubic root of 199991069 is about 584.7948427122.

The spelling of 199991069 in words is "one hundred ninety-nine million, nine hundred ninety-one thousand, sixty-nine".