669120516209 has 2 divisors, whose sum is σ = 669120516210. Its totient is φ = 669120516208.

The previous prime is 669120516199. The next prime is 669120516217. The reversal of 669120516209 is 902615021966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 386019903025 + 283100613184 = 621305^2 + 532072^2 .

It is a cyclic number.

It is not a de Polignac number, because 669120516209 - 2³⁶ = 600401039473 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (669120516269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334560258104 + 334560258105.

It is an arithmetic number, because the mean of its divisors is an integer number (334560258105).

Almost surely, 2^669120516209 is an apocalyptic number.

It is an amenable number.

669120516209 is a deficient number, since it is larger than the sum of its proper divisors (1).

669120516209 is an equidigital number, since it uses as much as digits as its factorization.

669120516209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 349920, while the sum is 47.

The spelling of 669120516209 in words is "six hundred sixty-nine billion, one hundred twenty million, five hundred sixteen thousand, two hundred nine".