129644789 has 4 divisors (see below), whose sum is σ = 129703200. Its totient is φ = 129586380.

The previous prime is 129644783. The next prime is 129644831. The reversal of 129644789 is 987446921.

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 a cyclic number.

It is not a de Polignac number, because 129644789 - 2⁴ = 129644773 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129644783) 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, 25739 + ... + 30360.

It is an arithmetic number, because the mean of its divisors is an integer number (32425800).

Almost surely, 2^129644789 is an apocalyptic number.

It is an amenable number.

129644789 is a deficient number, since it is larger than the sum of its proper divisors (58411).

129644789 is an equidigital number, since it uses as much as digits as its factorization.

129644789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58410.

The product of its digits is 870912, while the sum is 50.

The square root of 129644789 is about 11386.1665629833. The cubic root of 129644789 is about 506.1178895432.

The spelling of 129644789 in words is "one hundred twenty-nine million, six hundred forty-four thousand, seven hundred eighty-nine".