666611711 has 4 divisors (see below), whose sum is σ = 666663624. Its totient is φ = 666559800.

The previous prime is 666611707. The next prime is 666611773. The reversal of 666611711 is 117116666.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 117116666 = 2 ⋅58558333.

It is a cyclic number.

It is not a de Polignac number, because 666611711 - 2² = 666611707 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666611411) 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, 8981 + ... + 37601.

It is an arithmetic number, because the mean of its divisors is an integer number (166665906).

Almost surely, 2^666611711 is an apocalyptic number.

666611711 is a deficient number, since it is larger than the sum of its proper divisors (51913).

666611711 is a wasteful number, since it uses less digits than its factorization.

666611711 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51912.

The product of its digits is 9072, while the sum is 35.

The square root of 666611711 is about 25818.8247408746. The cubic root of 666611711 is about 873.5564599783.

The spelling of 666611711 in words is "six hundred sixty-six million, six hundred eleven thousand, seven hundred eleven".