66111 has 4 divisors (see below), whose sum is σ = 88152. Its totient is φ = 44072.

The previous prime is 66109. The next prime is 66137. The reversal of 66111 is 11166.

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 66111 - 2¹ = 66109 is a prime.

It is a D-number.

66111 is a modest number, since divided by 111 gives 66 as remainder.

It is a nialpdrome in base 10.

It is a zygodrome in base 10.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66161) 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, 11016 + ... + 11021.

It is an arithmetic number, because the mean of its divisors is an integer number (22038).

2⁶⁶¹¹¹ is an apocalyptic number.

66111 is a deficient number, since it is larger than the sum of its proper divisors (22041).

66111 is a wasteful number, since it uses less digits than its factorization.

66111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22040.

The product of its digits is 36, while the sum is 15.

The square root of 66111 is about 257.1205942744. The cubic root of 66111 is about 40.4350429538.

Adding to 66111 its reverse (11166), we get a palindrome (77277).

Subtracting from 66111 its reverse (11166), we obtain a palindrome (54945).

The spelling of 66111 in words is "sixty-six thousand, one hundred eleven".