165666128 has 40 divisors (see below), whose sum is σ = 328559328. Its totient is φ = 80892032.

The previous prime is 165666121. The next prime is 165666133. The reversal of 165666128 is 821666561.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165666121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 293975 + ... + 294537.

Almost surely, 2^165666128 is an apocalyptic number.

It is an amenable number.

165666128 is a deficient number, since it is larger than the sum of its proper divisors (162893200).

165666128 is a wasteful number, since it uses less digits than its factorization.

165666128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971 (or 965 counting only the distinct ones).

The product of its digits is 103680, while the sum is 41.

The square root of 165666128 is about 12871.1354588474. The cubic root of 165666128 is about 549.2177618174.

The spelling of 165666128 in words is "one hundred sixty-five million, six hundred sixty-six thousand, one hundred twenty-eight".