165565660 has 48 divisors (see below), whose sum is σ = 377368992. Its totient is φ = 60652800.

The previous prime is 165565657. The next prime is 165565663. The reversal of 165565660 is 66565561.

It is an interprime number because it is at equal distance from previous prime (165565657) and next prime (165565663).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165565663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31630 + ... + 36490.

It is an arithmetic number, because the mean of its divisors is an integer number (7861854).

Almost surely, 2^165565660 is an apocalyptic number.

165565660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 165565660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188684496).

165565660 is an abundant number, since it is smaller than the sum of its proper divisors (211803332).

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

165565660 is a wasteful number, since it uses less digits than its factorization.

165565660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5014 (or 5012 counting only the distinct ones).

The product of its (nonzero) digits is 162000, while the sum is 40.

The square root of 165565660 is about 12867.2320255757. The cubic root of 165565660 is about 549.1067152426.

Subtracting from 165565660 its reverse (66565561), we obtain a palindrome (99000099).

The spelling of 165565660 in words is "one hundred sixty-five million, five hundred sixty-five thousand, six hundred sixty".