129040813 has 12 divisors (see below), whose sum is σ = 142488220. Its totient is φ = 116772480.

The previous prime is 129040811. The next prime is 129040831. The reversal of 129040813 is 318040921.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 70257924 + 58782889 = 8382^2 + 7667^2 .

It is not a de Polignac number, because 129040813 - 2¹ = 129040811 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 (129040811) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 25381 + ... + 30037.

Almost surely, 2^129040813 is an apocalyptic number.

It is an amenable number.

129040813 is a deficient number, since it is larger than the sum of its proper divisors (13447407).

129040813 is a wasteful number, since it uses less digits than its factorization.

129040813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4908 (or 4897 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 129040813 is about 11359.6132416557. The cubic root of 129040813 is about 505.3307156344.

It can be divided in two parts, 1290408 and 13, that added together give a triangular number (1290421 = T₁₆₀₆).

The spelling of 129040813 in words is "one hundred twenty-nine million, forty thousand, eight hundred thirteen".