66559 has 4 divisors (see below), whose sum is σ = 67320. Its totient is φ = 65800.

The previous prime is 66553. The next prime is 66569. The reversal of 66559 is 95566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 66559 - 2⁷ = 66431 is a prime.

It is a Duffinian number.

66559 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 66559.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 229 + ... + 430.

It is an arithmetic number, because the mean of its divisors is an integer number (16830).

2⁶⁶⁵⁵⁹ is an apocalyptic number.

66559 is a deficient number, since it is larger than the sum of its proper divisors (761).

66559 is a wasteful number, since it uses less digits than its factorization.

66559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760.

The product of its digits is 8100, while the sum is 31.

The square root of 66559 is about 257.9903098955. The cubic root of 66559 is about 40.5261731952.

It can be divided in two parts, 6655 and 9, that multiplied together give a palindrome (59895).

The spelling of 66559 in words is "sixty-six thousand, five hundred fifty-nine".