199999001 has 2 divisors, whose sum is σ = 199999002. Its totient is φ = 199999000.

The previous prime is 199998989. The next prime is 199999043. The reversal of 199999001 is 100999991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198105625 + 1893376 = 14075^2 + 1376^2 .

It is a cyclic number.

It is not a de Polignac number, because 199999001 - 2¹⁰ = 199997977 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (199999061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99999500 + 99999501.

It is an arithmetic number, because the mean of its divisors is an integer number (99999501).

Almost surely, 2^199999001 is an apocalyptic number.

It is an amenable number.

199999001 is a deficient number, since it is larger than the sum of its proper divisors (1).

199999001 is an equidigital number, since it uses as much as digits as its factorization.

199999001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 59049, while the sum is 47.

The square root of 199999001 is about 14142.1003037031. The cubic root of 199999001 is about 584.8025739430.

The spelling of 199999001 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, one".