666656011 has 4 divisors (see below), whose sum is σ = 761892592. Its totient is φ = 571419432.

The previous prime is 666656009. The next prime is 666656027. The reversal of 666656011 is 110656666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 110656666 = 2 ⋅55328333.

It is a cyclic number.

It is not a de Polignac number, because 666656011 - 2¹ = 666656009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666656041) 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, 47618280 + ... + 47618293.

It is an arithmetic number, because the mean of its divisors is an integer number (190473148).

Almost surely, 2^666656011 is an apocalyptic number.

666656011 is a deficient number, since it is larger than the sum of its proper divisors (95236581).

666656011 is an equidigital number, since it uses as much as digits as its factorization.

666656011 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95236580.

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

The square root of 666656011 is about 25819.6826277939. The cubic root of 666656011 is about 873.5758104204.

The spelling of 666656011 in words is "six hundred sixty-six million, six hundred fifty-six thousand, eleven".