It is an unprimeable number.
Almost surely, 21166386818 is an apocalyptic number.
It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.
1166386818 is a wasteful number, since it uses less digits than its factorization.
1166386818 is an evil number, because the sum of its binary digits is even.
The sum of its prime factors is 72209.
The square root of 1166386818 is about 34152.4057424949. The cubic root of 1166386818 is about 1052.6424202683.
The spelling of 1166386818 in words is "one billion, one hundred sixty-six million, three hundred eighty-six thousand, eight hundred eighteen".