66240783279209 has 16 divisors (see below), whose sum is σ = 82589833798656. Its totient is φ = 51613743402000.

The previous prime is 66240783279133. The next prime is 66240783279217. The reversal of 66240783279209 is 90297238704266.

It is a cyclic number.

It is not a de Polignac number, because 66240783279209 - 2⁴⁰ = 65141271651433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66240783279259) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18795317 + ... + 22039634.

It is an arithmetic number, because the mean of its divisors is an integer number (5161864612416).

Almost surely, 2^{66240783279209} is an apocalyptic number.

It is an amenable number.

66240783279209 is a deficient number, since it is larger than the sum of its proper divisors (16349050519447).

66240783279209 is a wasteful number, since it uses less digits than its factorization.

66240783279209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40856036.

The product of its (nonzero) digits is 109734912, while the sum is 65.

The spelling of 66240783279209 in words is "sixty-six trillion, two hundred forty billion, seven hundred eighty-three million, two hundred seventy-nine thousand, two hundred nine".