165565560 has 64 divisors (see below), whose sum is σ = 497635200. Its totient is φ = 44067456.

The previous prime is 165565549. The next prime is 165565579. The reversal of 165565560 is 65565561.

It is a super-2 number, since 2×165565560² = 54823909316227200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87747 + ... + 89613.

It is an arithmetic number, because the mean of its divisors is an integer number (7775550).

Almost surely, 2^165565560 is an apocalyptic number.

165565560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165565560 is an abundant number, since it is smaller than the sum of its proper divisors (332069640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

165565560 is a wasteful number, since it uses less digits than its factorization.

165565560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2620 (or 2616 counting only the distinct ones).

The product of its (nonzero) digits is 135000, while the sum is 39.

The square root of 165565560 is about 12867.2281397355. The cubic root of 165565560 is about 549.1066046909.

Subtracting from 165565560 its reverse (65565561), we obtain a palindrome (99999999).

The spelling of 165565560 in words is "one hundred sixty-five million, five hundred sixty-five thousand, five hundred sixty".