129520129 has 2 divisors, whose sum is σ = 129520130. Its totient is φ = 129520128.

The previous prime is 129520121. The next prime is 129520151. The reversal of 129520129 is 921025921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 123988225 + 5531904 = 11135^2 + 2352^2 .

It is a cyclic number.

It is not a de Polignac number, because 129520129 - 2³ = 129520121 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 129520129.

It is not a weakly prime, because it can be changed into another prime (129520121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64760064 + 64760065.

It is an arithmetic number, because the mean of its divisors is an integer number (64760065).

Almost surely, 2^129520129 is an apocalyptic number.

It is an amenable number.

129520129 is a deficient number, since it is larger than the sum of its proper divisors (1).

129520129 is an equidigital number, since it uses as much as digits as its factorization.

129520129 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 129520129 is about 11380.6910598610. The cubic root of 129520129 is about 505.9556182334.

The spelling of 129520129 in words is "one hundred twenty-nine million, five hundred twenty thousand, one hundred twenty-nine".