129824209 has 2 divisors, whose sum is σ = 129824210. Its totient is φ = 129824208.

The previous prime is 129824197. The next prime is 129824221. The reversal of 129824209 is 902428921.

It is a balanced prime because it is at equal distance from previous prime (129824197) and next prime (129824221).

It can be written as a sum of positive squares in only one way, i.e., 128323584 + 1500625 = 11328^2 + 1225^2 .

It is a cyclic number.

It is not a de Polignac number, because 129824209 - 2⁹ = 129823697 is a prime.

It is not a weakly prime, because it can be changed into another prime (129824239) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64912104 + 64912105.

It is an arithmetic number, because the mean of its divisors is an integer number (64912105).

Almost surely, 2^129824209 is an apocalyptic number.

It is an amenable number.

129824209 is a deficient number, since it is larger than the sum of its proper divisors (1).

129824209 is an equidigital number, since it uses as much as digits as its factorization.

129824209 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 129824209 is about 11394.0426978312. The cubic root of 129824209 is about 506.3512600576.

The spelling of 129824209 in words is "one hundred twenty-nine million, eight hundred twenty-four thousand, two hundred nine".