165686560 has 48 divisors (see below), whose sum is σ = 421550136. Its totient is φ = 61175808.

The previous prime is 165686557. The next prime is 165686569. The reversal of 165686560 is 65686561.

It can be written as a sum of positive squares in 4 ways, for example, as 130782096 + 34904464 = 11436^2 + 5908^2 .

It is not an unprimeable number, because it can be changed into a prime (165686569) 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, 37749 + ... + 41908.

Almost surely, 2^165686560 is an apocalyptic number.

165686560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

165686560 is an abundant number, since it is smaller than the sum of its proper divisors (255863576).

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

165686560 is a wasteful number, since it uses less digits than its factorization.

165686560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79685 (or 79677 counting only the distinct ones).

The product of its (nonzero) digits is 259200, while the sum is 43.

The square root of 165686560 is about 12871.9291483445. The cubic root of 165686560 is about 549.2403396695.

Subtracting from 165686560 its reverse (65686561), we obtain a palindrome (99999999).

The spelling of 165686560 in words is "one hundred sixty-five million, six hundred eighty-six thousand, five hundred sixty".