660646 has 8 divisors (see below), whose sum is σ = 1132560. Its totient is φ = 283128.

The previous prime is 660643. The next prime is 660659. The reversal of 660646 is 646066.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660643) 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, 23581 + ... + 23608.

It is an arithmetic number, because the mean of its divisors is an integer number (141570).

2⁶⁶⁰⁶⁴⁶ is an apocalyptic number.

660646 is a deficient number, since it is larger than the sum of its proper divisors (471914).

660646 is a wasteful number, since it uses less digits than its factorization.

660646 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47198.

The product of its (nonzero) digits is 5184, while the sum is 28.

The square root of 660646 is about 812.8013287391. The cubic root of 660646 is about 87.0942739905.

The spelling of 660646 in words is "six hundred sixty thousand, six hundred forty-six".