165665212 has 12 divisors (see below), whose sum is σ = 293584480. Its totient is φ = 81783936.

The previous prime is 165665207. The next prime is 165665239. The reversal of 165665212 is 212566561.

It is a congruent 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 3 ways as a sum of consecutive naturals, for example, 261813 + ... + 262444.

Almost surely, 2^165665212 is an apocalyptic number.

It is an amenable number.

165665212 is a deficient number, since it is larger than the sum of its proper divisors (127919268).

165665212 is a wasteful number, since it uses less digits than its factorization.

165665212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 524340 (or 524338 counting only the distinct ones).

The product of its digits is 21600, while the sum is 34.

The square root of 165665212 is about 12871.0998753020. The cubic root of 165665212 is about 549.2167495719.

The spelling of 165665212 in words is "one hundred sixty-five million, six hundred sixty-five thousand, two hundred twelve".