129309813 has 12 divisors (see below), whose sum is σ = 189843628. Its totient is φ = 84792960.

The previous prime is 129309793. The next prime is 129309823. The reversal of 129309813 is 318903921.

It can be written as a sum of positive squares in 2 ways, for example, as 3017169 + 126292644 = 1737^2 + 11238^2 .

It is not a de Polignac number, because 129309813 - 2¹⁰ = 129308789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129309823) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 117220 + ... + 118317.

Almost surely, 2^129309813 is an apocalyptic number.

It is an amenable number.

129309813 is a deficient number, since it is larger than the sum of its proper divisors (60533815).

129309813 is a wasteful number, since it uses less digits than its factorization.

129309813 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235604 (or 235601 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 129309813 is about 11371.4472693673. The cubic root of 129309813 is about 505.6816113758.

The spelling of 129309813 in words is "one hundred twenty-nine million, three hundred nine thousand, eight hundred thirteen".