198137491 has 8 divisors (see below), whose sum is σ = 209382480. Its totient is φ = 186974208.

The previous prime is 198137473. The next prime is 198137497. The reversal of 198137491 is 194731891.

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 198137491 - 2⁹ = 198136979 is a prime.

It is a super-3 number, since 3×198137491³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (198137497) 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, 15406 + ... + 25171.

It is an arithmetic number, because the mean of its divisors is an integer number (26172810).

Almost surely, 2^198137491 is an apocalyptic number.

198137491 is a deficient number, since it is larger than the sum of its proper divisors (11244989).

198137491 is a wasteful number, since it uses less digits than its factorization.

198137491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40853.

The product of its digits is 54432, while the sum is 43.

The square root of 198137491 is about 14076.1319615866. The cubic root of 198137491 is about 582.9825467209.

The spelling of 198137491 in words is "one hundred ninety-eight million, one hundred thirty-seven thousand, four hundred ninety-one".