198918786816 has 108 divisors (see below), whose sum is σ = 573662801712. Its totient is φ = 66291130368.

The previous prime is 198918786779. The next prime is 198918786863. The reversal of 198918786816 is 618687819891.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15146845 + ... + 15159971.

Almost surely, 2^198918786816 is an apocalyptic number.

198918786816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 198918786816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (286831400856).

198918786816 is an abundant number, since it is smaller than the sum of its proper divisors (374744014896).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

198918786816 is a wasteful number, since it uses less digits than its factorization.

198918786816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19726 (or 19709 counting only the distinct ones).

The product of its digits is 83607552, while the sum is 72.

The spelling of 198918786816 in words is "one hundred ninety-eight billion, nine hundred eighteen million, seven hundred eighty-six thousand, eight hundred sixteen".