129752209 has 2 divisors, whose sum is σ = 129752210. Its totient is φ = 129752208.

The previous prime is 129752201. The next prime is 129752213. The reversal of 129752209 is 902257921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 110145025 + 19607184 = 10495^2 + 4428^2 .

It is a cyclic number.

It is not a de Polignac number, because 129752209 - 2³ = 129752201 is a prime.

It is not a weakly prime, because it can be changed into another prime (129752201) 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 as a sum of consecutive naturals, namely, 64876104 + 64876105.

It is an arithmetic number, because the mean of its divisors is an integer number (64876105).

Almost surely, 2^129752209 is an apocalyptic number.

It is an amenable number.

129752209 is a deficient number, since it is larger than the sum of its proper divisors (1).

129752209 is an equidigital number, since it uses as much as digits as its factorization.

129752209 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22680, while the sum is 37.

The square root of 129752209 is about 11390.8827138199. The cubic root of 129752209 is about 506.2576359362.

The spelling of 129752209 in words is "one hundred twenty-nine million, seven hundred fifty-two thousand, two hundred nine".