199999999918 has 8 divisors (see below), whose sum is σ = 302189781312. Its totient is φ = 99270072816.

The previous prime is 199999999891. The next prime is 199999999921. The reversal of 199999999918 is 819999999991.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364963230 + ... + 364963777.

It is an arithmetic number, because the mean of its divisors is an integer number (37773722664).

Almost surely, 2^199999999918 is an apocalyptic number.

199999999918 is a deficient number, since it is larger than the sum of its proper divisors (102189781394).

199999999918 is a wasteful number, since it uses less digits than its factorization.

199999999918 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729927146.

The product of its digits is 3099363912, while the sum is 91.

The spelling of 199999999918 in words is "one hundred ninety-nine billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred eighteen".