166802812225 has 45 divisors (see below), whose sum is σ = 241438544867. Its totient is φ = 114310457520.

The previous prime is 166802812207. The next prime is 166802812289. The reversal of 166802812225 is 522218208661.

The square root of 166802812225 is 408415.

It is a perfect power (a square), and thus also a powerful number.

166802812225 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 60049012401 + 106753799824 = 245049^2 + 326732^2 .

It is not a de Polignac number, because 166802812225 - 2⁷ = 166802812097 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 100060842 + ... + 100062508.

Almost surely, 2^166802812225 is an apocalyptic number.

166802812225 is the 408415-th square number.

166802812225 is the 204208-th centered octagonal number.

It is an amenable number.

166802812225 is a deficient number, since it is larger than the sum of its proper divisors (74635732642).

166802812225 is an frugal number, since it uses more digits than its factorization.

166802812225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3372 (or 1679 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 43.

The spelling of 166802812225 in words is "one hundred sixty-six billion, eight hundred two million, eight hundred twelve thousand, two hundred twenty-five".