129306813 has 4 divisors (see below), whose sum is σ = 172409088. Its totient is φ = 86204540.

The previous prime is 129306787. The next prime is 129306839. The reversal of 129306813 is 318603921.

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 an interprime number because it is at equal distance from previous prime (129306787) and next prime (129306839).

It is a cyclic number.

It is not a de Polignac number, because 129306813 - 2⁵ = 129306781 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129306883) 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, 21551133 + ... + 21551138.

It is an arithmetic number, because the mean of its divisors is an integer number (43102272).

Almost surely, 2^129306813 is an apocalyptic number.

It is an amenable number.

129306813 is a deficient number, since it is larger than the sum of its proper divisors (43102275).

129306813 is an equidigital number, since it uses as much as digits as its factorization.

129306813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43102274.

The product of its (nonzero) digits is 7776, while the sum is 33.

The square root of 129306813 is about 11371.3153592713. The cubic root of 129306813 is about 505.6777007250.

The spelling of 129306813 in words is "one hundred twenty-nine million, three hundred six thousand, eight hundred thirteen".