129009911212009 has 9 divisors (see below), whose sum is σ = 129086795579077. Its totient is φ = 128933072630464.

The previous prime is 129009911211991. The next prime is 129009911212079. The reversal of 129009911212009 is 900212119900921.

The square root of 129009911212009 is 11358253.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 68444597265625 + 60565313946384 = 8273125^2 + 7782372^2 .

It is not a de Polignac number, because 129009911212009 - 2²⁹ = 129009374341097 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 129009911212009.

It is not an unprimeable number, because it can be changed into a prime (129009911212079) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 35085641679 + ... + 35085645355.

Almost surely, 2^{129009911212009} is an apocalyptic number.

129009911212009 is the 11358253-rd square number.

129009911212009 is the 5679127-th centered octagonal number.

It is an amenable number.

129009911212009 is a deficient number, since it is larger than the sum of its proper divisors (76884367068).

129009911212009 is an frugal number, since it uses more digits than its factorization.

129009911212009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13532 (or 6766 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 46.

The spelling of 129009911212009 in words is "one hundred twenty-nine trillion, nine billion, nine hundred eleven million, two hundred twelve thousand, nine".