660560 has 40 divisors (see below), whose sum is σ = 1607040. Its totient is φ = 252032.

The previous prime is 660559. The next prime is 660563. The reversal of 660560 is 65066.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (23).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660563) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1661 + ... + 2019.

It is an arithmetic number, because the mean of its divisors is an integer number (40176).

2⁶⁶⁰⁵⁶⁰ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 660560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (803520).

660560 is an abundant number, since it is smaller than the sum of its proper divisors (946480).

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

660560 is a wasteful number, since it uses less digits than its factorization.

660560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 395 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 23.

The square root of 660560 is about 812.7484235605. The cubic root of 660560 is about 87.0904946429.

The spelling of 660560 in words is "six hundred sixty thousand, five hundred sixty".