666560611 has 4 divisors (see below), whose sum is σ = 667674000. Its totient is φ = 665447224.

The previous prime is 666560581. The next prime is 666560617. The reversal of 666560611 is 116065666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 116065666 = 2 ⋅58032833.

It is a cyclic number.

It is not a de Polignac number, because 666560611 - 2⁵ = 666560579 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666560617) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 555796 + ... + 556993.

It is an arithmetic number, because the mean of its divisors is an integer number (166918500).

Almost surely, 2^666560611 is an apocalyptic number.

666560611 is a deficient number, since it is larger than the sum of its proper divisors (1113389).

666560611 is a wasteful number, since it uses less digits than its factorization.

666560611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1113388.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 666560611 is about 25817.8351338760. The cubic root of 666560611 is about 873.5341382003.

It can be divided in two parts, 6665 and 60611, that added together give a palindrome (67276).

The spelling of 666560611 in words is "six hundred sixty-six million, five hundred sixty thousand, six hundred eleven".