129746201209 has 9 divisors (see below), whose sum is σ = 135641268399. Its totient is φ = 124097137560.

The previous prime is 129746201161. The next prime is 129746201243. The reversal of 129746201209 is 902102647921.

The square root of 129746201209 is 360203.

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

It can be written as a sum of positive squares in only one way, i.e., 128555951209 + 1190250000 = 358547^2 + 34500^2 .

It is not a de Polignac number, because 129746201209 - 2⁹ = 129746200697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129746201269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 8276839 + ... + 8292499.

Almost surely, 2^129746201209 is an apocalyptic number.

129746201209 is the 360203-rd square number.

129746201209 is the 180102-nd centered octagonal number.

It is an amenable number.

129746201209 is a deficient number, since it is larger than the sum of its proper divisors (5895067190).

129746201209 is an frugal number, since it uses more digits than its factorization.

129746201209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31368 (or 15684 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 43.

The spelling of 129746201209 in words is "one hundred twenty-nine billion, seven hundred forty-six million, two hundred one thousand, two hundred nine".