199558987 has 4 divisors (see below), whose sum is σ = 199587976. Its totient is φ = 199530000.

The previous prime is 199558979. The next prime is 199558993. The reversal of 199558987 is 789855991.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 199558987 - 2³ = 199558979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (199558927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2383 + ... + 20119.

It is an arithmetic number, because the mean of its divisors is an integer number (49896994).

Almost surely, 2^199558987 is an apocalyptic number.

199558987 is a deficient number, since it is larger than the sum of its proper divisors (28989).

199558987 is a wasteful number, since it uses less digits than its factorization.

199558987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28988.

The product of its digits is 8164800, while the sum is 61.

The square root of 199558987 is about 14126.5348546627. The cubic root of 199558987 is about 584.3733880326.

The spelling of 199558987 in words is "one hundred ninety-nine million, five hundred fifty-eight thousand, nine hundred eighty-seven".