660613 has 4 divisors (see below), whose sum is σ = 662508. Its totient is φ = 658720.

The previous prime is 660607. The next prime is 660617. The reversal of 660613 is 316066.

660613 is nontrivially palindromic in base 15.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 388129 + 272484 = 623^2 + 522^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-660613 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (660617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 256 + ... + 1177.

It is an arithmetic number, because the mean of its divisors is an integer number (165627).

2⁶⁶⁰⁶¹³ is an apocalyptic number.

It is an amenable number.

660613 is a deficient number, since it is larger than the sum of its proper divisors (1895).

660613 is a wasteful number, since it uses less digits than its factorization.

660613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1894.

The product of its (nonzero) digits is 648, while the sum is 22.

The square root of 660613 is about 812.7810283219. The cubic root of 660613 is about 87.0928238145.

Adding to 660613 its reverse (316066), we get a palindrome (976679).

The spelling of 660613 in words is "six hundred sixty thousand, six hundred thirteen".