660520 has 48 divisors (see below), whose sum is σ = 1733940. Its totient is φ = 225792.

The previous prime is 660509. The next prime is 660521. The reversal of 660520 is 25066.

It can be written as a sum of positive squares in 2 ways, for example, as 636804 + 23716 = 798^2 + 154^2 .

It is not an unprimeable number, because it can be changed into a prime (660521) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1792 + ... + 2128.

2⁶⁶⁰⁵²⁰ 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 660520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (866970).

660520 is an abundant number, since it is smaller than the sum of its proper divisors (1073420).

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

660520 is a wasteful number, since it uses less digits than its factorization.

660520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 362 (or 351 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 660520 is about 812.7238153272. The cubic root of 660520 is about 87.0887366951.

Adding to 660520 its reverse (25066), we get a palindrome (685586).

The spelling of 660520 in words is "six hundred sixty thousand, five hundred twenty".