660764 has 24 divisors (see below), whose sum is σ = 1267728. Its totient is φ = 299520.

The previous prime is 660757. The next prime is 660769. The reversal of 660764 is 467066.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660769) by changing a digit.

660764 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4979 + ... + 5109.

It is an arithmetic number, because the mean of its divisors is an integer number (52822).

2⁶⁶⁰⁷⁶⁴ is an apocalyptic number.

It is an amenable number.

660764 is a deficient number, since it is larger than the sum of its proper divisors (606964).

660764 is a wasteful number, since it uses less digits than its factorization.

660764 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 245 (or 243 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 660764 is about 812.8739139621. The cubic root of 660764 is about 87.0994590732.

The spelling of 660764 in words is "six hundred sixty thousand, seven hundred sixty-four".