66320 has 20 divisors (see below), whose sum is σ = 154380. Its totient is φ = 26496.

The previous prime is 66301. The next prime is 66337. The reversal of 66320 is 2366.

It can be written as a sum of positive squares in 2 ways, for example, as 30976 + 35344 = 176^2 + 188^2 .

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

It is a nialpdrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 335 + ... + 494.

It is an arithmetic number, because the mean of its divisors is an integer number (7719).

2⁶⁶³²⁰ is an apocalyptic number.

It is an amenable number.

66320 is an abundant number, since it is smaller than the sum of its proper divisors (88060).

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 (77190).

66320 is a wasteful number, since it uses less digits than its factorization.

66320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 842 (or 836 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 17.

The square root of 66320 is about 257.5266976451. The cubic root of 66320 is about 40.4776079033.

Adding to 66320 its reverse (2366), we get a palindrome (68686).

The spelling of 66320 in words is "sixty-six thousand, three hundred twenty".