66756 has 12 divisors (see below), whose sum is σ = 155792. Its totient is φ = 22248.

The previous prime is 66751. The next prime is 66763. The reversal of 66756 is 65766.

It is a tau number, because it is divible by the number of its divisors (12).

It is not an unprimeable number, because it can be changed into a prime (66751) by changing a digit.

66756 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, 2770 + ... + 2793.

2⁶⁶⁷⁵⁶ is an apocalyptic number.

It is an amenable number.

66756 is an abundant number, since it is smaller than the sum of its proper divisors (89036).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

It is a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77896).

66756 is a wasteful number, since it uses less digits than its factorization.

66756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5570 (or 5568 counting only the distinct ones).

The product of its digits is 7560, while the sum is 30.

The square root of 66756 is about 258.3718250893. The cubic root of 66756 is about 40.5661166660.

Subtracting from 66756 its reverse (65766), we obtain a triangular number (990 = T₄₄).

The spelling of 66756 in words is "sixty-six thousand, seven hundred fifty-six".