129284209 has 4 divisors (see below), whose sum is σ = 129820900. Its totient is φ = 128747520.

The previous prime is 129284153. The next prime is 129284231. The reversal of 129284209 is 902482921.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 118374400 + 10909809 = 10880^2 + 3303^2 .

It is a cyclic number.

It is not a de Polignac number, because 129284209 - 2²³ = 120895601 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129284249) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 267984 + ... + 268465.

It is an arithmetic number, because the mean of its divisors is an integer number (32455225).

Almost surely, 2^129284209 is an apocalyptic number.

It is an amenable number.

129284209 is a deficient number, since it is larger than the sum of its proper divisors (536691).

129284209 is an equidigital number, since it uses as much as digits as its factorization.

129284209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 536690.

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

The square root of 129284209 is about 11370.3214114641. The cubic root of 129284209 is about 505.6482333299.

The spelling of 129284209 in words is "one hundred twenty-nine million, two hundred eighty-four thousand, two hundred nine".