It is a strong prime.
It is an emirp because it is prime and its reverse (188089661) is a distict prime. It is also a bemirp because it and its reverse can be mirrored producing other two distinct primes, 188086991 and 199680881.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-166980881 is a prime.
It is a Chen prime.
Almost surely, 2166980881 is an apocalyptic number.
It is an amenable number.
166980881 is an equidigital number, since it uses as much as digits as its factorization.
166980881 is an evil number, because the sum of its binary digits is even.
The square root of 166980881 is about 12922.1082258275. The cubic root of 166980881 is about 550.6668286652. Note that the first 3 decimals are identical.
The spelling of 166980881 in words is "one hundred sixty-six million, nine hundred eighty thousand, eight hundred eighty-one".