165557609 has 8 divisors (see below), whose sum is σ = 189309120. Its totient is φ = 141831216.

The previous prime is 165557591. The next prime is 165557677. The reversal of 165557609 is 906755561.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 165557609 - 2¹² = 165553513 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 165557609.

It is not an unprimeable number, because it can be changed into a prime (165557699) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11042 + ... + 21284.

It is an arithmetic number, because the mean of its divisors is an integer number (23663640).

Almost surely, 2^165557609 is an apocalyptic number.

It is an amenable number.

165557609 is a deficient number, since it is larger than the sum of its proper divisors (23751511).

165557609 is a wasteful number, since it uses less digits than its factorization.

165557609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12559.

The product of its (nonzero) digits is 283500, while the sum is 44.

The square root of 165557609 is about 12866.9191728245. The cubic root of 165557609 is about 549.0978145849.

The spelling of 165557609 in words is "one hundred sixty-five million, five hundred fifty-seven thousand, six hundred nine".