198381391 has 8 divisors (see below), whose sum is σ = 213789744. Its totient is φ = 182994240.

The previous prime is 198381389. The next prime is 198381397. The reversal of 198381391 is 193183891.

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

It is not a de Polignac number, because 198381391 - 2¹ = 198381389 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 (198381397) 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, 17940 + ... + 26806.

It is an arithmetic number, because the mean of its divisors is an integer number (26723718).

Almost surely, 2^198381391 is an apocalyptic number.

198381391 is a deficient number, since it is larger than the sum of its proper divisors (15408353).

198381391 is a wasteful number, since it uses less digits than its factorization.

198381391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10601.

The product of its digits is 46656, while the sum is 43.

The square root of 198381391 is about 14084.7928987259. The cubic root of 198381391 is about 583.2216586947.

The spelling of 198381391 in words is "one hundred ninety-eight million, three hundred eighty-one thousand, three hundred ninety-one".