660684 has 12 divisors (see below), whose sum is σ = 1541624. Its totient is φ = 220224.

The previous prime is 660683. The next prime is 660719. The reversal of 660684 is 486066.

It is a happy number.

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

It is a super-3 number, since 3×660684³ = 865172333624680512, which contains 333 as substring.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (660683) 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, 27517 + ... + 27540.

2⁶⁶⁰⁶⁸⁴ is an apocalyptic number.

It is an amenable number.

660684 is an abundant number, since it is smaller than the sum of its proper divisors (880940).

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

660684 is a wasteful number, since it uses less digits than its factorization.

660684 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55064 (or 55062 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 660684 is about 812.8247043490. The cubic root of 660684 is about 87.0959438303.

The spelling of 660684 in words is "six hundred sixty thousand, six hundred eighty-four".