It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 99266 = 2 ⋅49633.
It is a cyclic number.
It is a de Polignac number, because none of the positive numbers 2k-66299 is a prime.
It is a Duffinian number.
It is a plaindrome in base 15.
266299 is an apocalyptic number.
66299 is a wasteful number, since it uses less digits than its factorization.
66299 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 564.
The square root of 66299 is about 257.4859219453. The cubic root of 66299 is about 40.4733350872.
The spelling of 66299 in words is "sixty-six thousand, two hundred ninety-nine".