65806 has 8 divisors (see below), whose sum is σ = 106344. Its totient is φ = 30360.

The previous prime is 65789. The next prime is 65809. The reversal of 65806 is 60856.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65809) by changing a digit.

65806 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1240 + ... + 1291.

It is an arithmetic number, because the mean of its divisors is an integer number (13293).

2⁶⁵⁸⁰⁶ is an apocalyptic number.

65806 is a deficient number, since it is larger than the sum of its proper divisors (40538).

65806 is a wasteful number, since it uses less digits than its factorization.

65806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2546.

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

The square root of 65806 is about 256.5268017187. The cubic root of 65806 is about 40.3727653586.

Subtracting from 65806 its reverse (60856), we obtain a triangular number (4950 = T₉₉).

The spelling of 65806 in words is "sixty-five thousand, eight hundred six".