66784 has 12 divisors (see below), whose sum is σ = 131544. Its totient is φ = 33376.

The previous prime is 66763. The next prime is 66791. The reversal of 66784 is 48766.

66784 is nontrivially palindromic in base 5.

It is a congruent number.

It is an unprimeable 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 as a sum of consecutive naturals, namely, 1012 + ... + 1075.

It is an arithmetic number, because the mean of its divisors is an integer number (10962).

2⁶⁶⁷⁸⁴ is an apocalyptic number.

It is an amenable number.

66784 is a deficient number, since it is larger than the sum of its proper divisors (64760).

66784 is a wasteful number, since it uses less digits than its factorization.

66784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2097 (or 2089 counting only the distinct ones).

The product of its digits is 8064, while the sum is 31.

The square root of 66784 is about 258.4260048834. The cubic root of 66784 is about 40.5717875295.

It can be divided in two parts, 6 and 6784, that multiplied together give a palindrome (40704).

The spelling of 66784 in words is "sixty-six thousand, seven hundred eighty-four".