660511 has 4 divisors (see below), whose sum is σ = 666792. Its totient is φ = 654232.

The previous prime is 660509. The next prime is 660521. The reversal of 660511 is 115066.

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

It is a cyclic number.

It is not a de Polignac number, because 660511 - 2¹ = 660509 is a prime.

It is a super-2 number, since 2×660511² = 872549562242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 2980 + ... + 3193.

It is an arithmetic number, because the mean of its divisors is an integer number (166698).

2⁶⁶⁰⁵¹¹ is an apocalyptic number.

660511 is a deficient number, since it is larger than the sum of its proper divisors (6281).

660511 is a wasteful number, since it uses less digits than its factorization.

660511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6280.

The product of its (nonzero) digits is 180, while the sum is 19.

The square root of 660511 is about 812.7182783720. The cubic root of 660511 is about 87.0883411470.

Adding to 660511 its reverse (115066), we get a palindrome (775577).

The spelling of 660511 in words is "six hundred sixty thousand, five hundred eleven".