129375817 has 2 divisors, whose sum is σ = 129375818. Its totient is φ = 129375816.

The previous prime is 129375811. The next prime is 129375821. The reversal of 129375817 is 718573921.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 129299641 + 76176 = 11371^2 + 276^2 .

It is a cyclic number.

It is not a de Polignac number, because 129375817 - 2¹⁹ = 128851529 is a prime.

It is not a weakly prime, because it can be changed into another prime (129375811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64687908 + 64687909.

It is an arithmetic number, because the mean of its divisors is an integer number (64687909).

Almost surely, 2^129375817 is an apocalyptic number.

It is an amenable number.

129375817 is a deficient number, since it is larger than the sum of its proper divisors (1).

129375817 is an equidigital number, since it uses as much as digits as its factorization.

129375817 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 105840, while the sum is 43.

The square root of 129375817 is about 11374.3490802771. The cubic root of 129375817 is about 505.7676356070.

The spelling of 129375817 in words is "one hundred twenty-nine million, three hundred seventy-five thousand, eight hundred seventeen".