199979989 has 8 divisors (see below), whose sum is σ = 218301120. Its totient is φ = 181682400.

The previous prime is 199979981. The next prime is 199979999. The reversal of 199979989 is 989979991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 199979989 - 2³ = 199979981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (199979981) 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 7 ways as a sum of consecutive naturals, for example, 15177 + ... + 25105.

It is an arithmetic number, because the mean of its divisors is an integer number (27287640).

Almost surely, 2^199979989 is an apocalyptic number.

It is an amenable number.

199979989 is a deficient number, since it is larger than the sum of its proper divisors (18321131).

199979989 is a wasteful number, since it uses less digits than its factorization.

199979989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11771.

The product of its digits is 29760696, while the sum is 70.

The square root of 199979989 is about 14141.4281103430. The cubic root of 199979989 is about 584.7840428191.

The spelling of 199979989 in words is "one hundred ninety-nine million, nine hundred seventy-nine thousand, nine hundred eighty-nine".