65680 has 20 divisors (see below), whose sum is σ = 152892. Its totient is φ = 26240.

The previous prime is 65677. The next prime is 65687. The reversal of 65680 is 8656.

It can be written as a sum of positive squares in 2 ways, for example, as 20736 + 44944 = 144^2 + 212^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a zygodrome in base 9.

It is not an unprimeable number, because it can be changed into a prime (65687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (3) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 331 + ... + 490.

2⁶⁵⁶⁸⁰ is an apocalyptic number.

It is an amenable number.

65680 is an abundant number, since it is smaller than the sum of its proper divisors (87212).

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

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (76446).

65680 is a wasteful number, since it uses less digits than its factorization.

65680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 834 (or 828 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 65680 is about 256.2810956743. The cubic root of 65680 is about 40.3469813946.

The spelling of 65680 in words is "sixty-five thousand, six hundred eighty".