199999905 has 16 divisors (see below), whose sum is σ = 365714304. Its totient is φ = 91428480.

The previous prime is 199999903. The next prime is 199999931. The reversal of 199999905 is 509999991.

It is not a de Polignac number, because 199999905 - 2¹ = 199999903 is a prime.

It is not an unprimeable number, because it can be changed into a prime (199999901) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 952276 + ... + 952485.

It is an arithmetic number, because the mean of its divisors is an integer number (22857144).

Almost surely, 2^199999905 is an apocalyptic number.

199999905 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

199999905 is a deficient number, since it is larger than the sum of its proper divisors (165714399).

199999905 is a wasteful number, since it uses less digits than its factorization.

199999905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1904776.

The product of its (nonzero) digits is 2657205, while the sum is 60.

The square root of 199999905 is about 14142.1322649733. The cubic root of 199999905 is about 584.8034550487.

The spelling of 199999905 in words is "one hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred five".