198389191091 has 12 divisors (see below), whose sum is σ = 245512914192. Its totient is φ = 156967271136.

The previous prime is 198389191067. The next prime is 198389191103. The reversal of 198389191091 is 190191983891.

It is not a de Polignac number, because 198389191091 - 2⁶ = 198389191027 is a prime.

It is a super-2 number, since 2×198389191091² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 198389191091.

It is not an unprimeable number, because it can be changed into a prime (198389191001) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 83848856 + ... + 83851221.

It is an arithmetic number, because the mean of its divisors is an integer number (20459409516).

Almost surely, 2^198389191091 is an apocalyptic number.

198389191091 is a deficient number, since it is larger than the sum of its proper divisors (47123723101).

198389191091 is a wasteful number, since it uses less digits than its factorization.

198389191091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167700110 (or 167700097 counting only the distinct ones).

The product of its (nonzero) digits is 1259712, while the sum is 59.

The spelling of 198389191091 in words is "one hundred ninety-eight billion, three hundred eighty-nine million, one hundred ninety-one thousand, ninety-one".