199818389 has 8 divisors (see below), whose sum is σ = 206359608. Its totient is φ = 193337280.

The previous prime is 199818347. The next prime is 199818401. The reversal of 199818389 is 983818991.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 20164 + 199798225 = 142^2 + 14135^2 .

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 199818389 - 2¹⁶ = 199752853 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 (199818329) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8222 + ... + 21615.

It is an arithmetic number, because the mean of its divisors is an integer number (25794951).

Almost surely, 2^199818389 is an apocalyptic number.

It is an amenable number.

199818389 is a deficient number, since it is larger than the sum of its proper divisors (6541219).

199818389 is a wasteful number, since it uses less digits than its factorization.

199818389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30055.

The product of its digits is 1119744, while the sum is 56.

The square root of 199818389 is about 14135.7132469501. The cubic root of 199818389 is about 584.6264827751.

The spelling of 199818389 in words is "one hundred ninety-nine million, eight hundred eighteen thousand, three hundred eighty-nine".