129201609 has 4 divisors (see below), whose sum is σ = 172268816. Its totient is φ = 86134404.

The previous prime is 129201593. The next prime is 129201613. The reversal of 129201609 is 906102921.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 129201609 - 2⁴ = 129201593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129201659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21533599 + ... + 21533604.

It is an arithmetic number, because the mean of its divisors is an integer number (43067204).

Almost surely, 2^129201609 is an apocalyptic number.

It is an amenable number.

129201609 is a deficient number, since it is larger than the sum of its proper divisors (43067207).

129201609 is an equidigital number, since it uses as much as digits as its factorization.

129201609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43067206.

The product of its (nonzero) digits is 1944, while the sum is 30.

The square root of 129201609 is about 11366.6885679163. The cubic root of 129201609 is about 505.5405237535.

The spelling of 129201609 in words is "one hundred twenty-nine million, two hundred one thousand, six hundred nine".