129280709 has 2 divisors, whose sum is σ = 129280710. Its totient is φ = 129280708.

The previous prime is 129280687. The next prime is 129280751. The reversal of 129280709 is 907082921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 109788484 + 19492225 = 10478^2 + 4415^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-129280709 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (129280799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64640354 + 64640355.

It is an arithmetic number, because the mean of its divisors is an integer number (64640355).

Almost surely, 2^129280709 is an apocalyptic number.

It is an amenable number.

129280709 is a deficient number, since it is larger than the sum of its proper divisors (1).

129280709 is an equidigital number, since it uses as much as digits as its factorization.

129280709 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 38.

The square root of 129280709 is about 11370.1675009650. The cubic root of 129280709 is about 505.6436702957.

The spelling of 129280709 in words is "one hundred twenty-nine million, two hundred eighty thousand, seven hundred nine".