66659 has 4 divisors (see below), whose sum is σ = 67200. Its totient is φ = 66120.

The previous prime is 66653. The next prime is 66683. The reversal of 66659 is 95666.

66659 is nontrivially palindromic in base 5.

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 66659 - 2⁴ = 66643 is a prime.

It is a Duffinian number.

Its product of digits (9720) is a multiple of the sum of its prime divisors (540).

It is a plaindrome in base 13.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17 + ... + 365.

It is an arithmetic number, because the mean of its divisors is an integer number (16800).

2⁶⁶⁶⁵⁹ is an apocalyptic number.

66659 is a deficient number, since it is larger than the sum of its proper divisors (541).

66659 is a wasteful number, since it uses less digits than its factorization.

66659 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 540.

The product of its digits is 9720, while the sum is 32.

The square root of 66659 is about 258.1840428841. The cubic root of 66659 is about 40.5464589037.

The spelling of 66659 in words is "sixty-six thousand, six hundred fifty-nine".