199531109 has 2 divisors, whose sum is σ = 199531110. Its totient is φ = 199531108.

The previous prime is 199531081. The next prime is 199531151. The reversal of 199531109 is 901135991.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 136773025 + 62758084 = 11695^2 + 7922^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-199531109 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (199533109) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99765554 + 99765555.

It is an arithmetic number, because the mean of its divisors is an integer number (99765555).

Almost surely, 2^199531109 is an apocalyptic number.

It is an amenable number.

199531109 is a deficient number, since it is larger than the sum of its proper divisors (1).

199531109 is an equidigital number, since it uses as much as digits as its factorization.

199531109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10935, while the sum is 38.

The square root of 199531109 is about 14125.5480955608. The cubic root of 199531109 is about 584.3461748257.

The spelling of 199531109 in words is "one hundred ninety-nine million, five hundred thirty-one thousand, one hundred nine".