66687 has 4 divisors (see below), whose sum is σ = 88920. Its totient is φ = 44456.

The previous prime is 66683. The next prime is 66697. The reversal of 66687 is 78666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66687 - 2² = 66683 is a prime.

It is a D-number.

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 (66683) 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, 11112 + ... + 11117.

It is an arithmetic number, because the mean of its divisors is an integer number (22230).

2⁶⁶⁶⁸⁷ is an apocalyptic number.

66687 is a deficient number, since it is larger than the sum of its proper divisors (22233).

66687 is a wasteful number, since it uses less digits than its factorization.

66687 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22232.

The product of its digits is 12096, while the sum is 33.

The square root of 66687 is about 258.2382620759. The cubic root of 66687 is about 40.5521352661.

The spelling of 66687 in words is "sixty-six thousand, six hundred eighty-seven".