666273885609 has 16 divisors (see below), whose sum is σ = 935138958080. Its totient is φ = 420796587600.

The previous prime is 666273885553. The next prime is 666273885643. The reversal of 666273885609 is 906588372666.

It is a happy number.

It is not a de Polignac number, because 666273885609 - 2⁷ = 666273885481 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 666273885609.

It is not an unprimeable number, because it can be changed into a prime (666273885709) 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 15 ways as a sum of consecutive naturals, for example, 4883214 + ... + 5017800.

It is an arithmetic number, because the mean of its divisors is an integer number (58446184880).

Almost surely, 2^666273885609 is an apocalyptic number.

It is an amenable number.

666273885609 is a deficient number, since it is larger than the sum of its proper divisors (268865072471).

666273885609 is a wasteful number, since it uses less digits than its factorization.

666273885609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221460.

The product of its (nonzero) digits is 156764160, while the sum is 66.

The spelling of 666273885609 in words is "six hundred sixty-six billion, two hundred seventy-three million, eight hundred eighty-five thousand, six hundred nine".