660784 has 10 divisors (see below), whose sum is σ = 1280300. Its totient is φ = 330384.

The previous prime is 660769. The next prime is 660787. The reversal of 660784 is 487066.

It is not an unprimeable number, because it can be changed into a prime (660787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20634 + ... + 20665.

It is an arithmetic number, because the mean of its divisors is an integer number (128030).

2⁶⁶⁰⁷⁸⁴ is an apocalyptic number.

It is an amenable number.

660784 is a deficient number, since it is larger than the sum of its proper divisors (619516).

660784 is a wasteful number, since it uses less digits than its factorization.

660784 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41307 (or 41301 counting only the distinct ones).

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

The square root of 660784 is about 812.8862158999. The cubic root of 660784 is about 87.1003378396.

It can be divided in two parts, 660 and 784, that added together give a square (1444 = 38²).

The spelling of 660784 in words is "six hundred sixty thousand, seven hundred eighty-four".