199890879 has 16 divisors (see below), whose sum is σ = 286986240. Its totient is φ = 123294080.

The previous prime is 199890869. The next prime is 199890893. The reversal of 199890879 is 978098991.

It is a cyclic number.

It is not a de Polignac number, because 199890879 - 2⁸ = 199890623 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199890829) 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 in 15 ways as a sum of consecutive naturals, for example, 30207 + ... + 36224.

It is an arithmetic number, because the mean of its divisors is an integer number (17936640).

Almost surely, 2^199890879 is an apocalyptic number.

199890879 is a deficient number, since it is larger than the sum of its proper divisors (87095361).

199890879 is a wasteful number, since it uses less digits than its factorization.

199890879 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66510.

The product of its (nonzero) digits is 2939328, while the sum is 60.

The square root of 199890879 is about 14138.2770873965. The cubic root of 199890879 is about 584.6971710472.

The spelling of 199890879 in words is "one hundred ninety-nine million, eight hundred ninety thousand, eight hundred seventy-nine".