165638812 has 6 divisors (see below), whose sum is σ = 289867928. Its totient is φ = 82819404.

The previous prime is 165638791. The next prime is 165638831. The reversal of 165638812 is 218836561.

It is a congruent number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 20704848 + ... + 20704855.

Almost surely, 2^165638812 is an apocalyptic number.

It is an amenable number.

165638812 is a deficient number, since it is larger than the sum of its proper divisors (124229116).

165638812 is a wasteful number, since it uses less digits than its factorization.

165638812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41409707 (or 41409705 counting only the distinct ones).

The product of its digits is 69120, while the sum is 40.

The square root of 165638812 is about 12870.0742810599. The cubic root of 165638812 is about 549.1875740794.

The spelling of 165638812 in words is "one hundred sixty-five million, six hundred thirty-eight thousand, eight hundred twelve".