129505399 has 2 divisors, whose sum is σ = 129505400. Its totient is φ = 129505398.

The previous prime is 129505391. The next prime is 129505423. The reversal of 129505399 is 993505921.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 129505399 - 2³ = 129505391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129505391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64752699 + 64752700.

It is an arithmetic number, because the mean of its divisors is an integer number (64752700).

Almost surely, 2^129505399 is an apocalyptic number.

129505399 is a deficient number, since it is larger than the sum of its proper divisors (1).

129505399 is an equidigital number, since it uses as much as digits as its factorization.

129505399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 109350, while the sum is 43.

The square root of 129505399 is about 11380.0438927097. The cubic root of 129505399 is about 505.9364371510.

The spelling of 129505399 in words is "one hundred twenty-nine million, five hundred five thousand, three hundred ninety-nine".