129840636 has 12 divisors (see below), whose sum is σ = 302961512. Its totient is φ = 43280208.

The previous prime is 129840631. The next prime is 129840653. The reversal of 129840636 is 636048921.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 129840594 and 129840603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129840631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5410015 + ... + 5410038.

Almost surely, 2^129840636 is an apocalyptic number.

It is an amenable number.

129840636 is an abundant number, since it is smaller than the sum of its proper divisors (173120876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

129840636 is a wasteful number, since it uses less digits than its factorization.

129840636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10820060 (or 10820058 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 129840636 is about 11394.7635341853. The cubic root of 129840636 is about 506.3726158109.

The spelling of 129840636 in words is "one hundred twenty-nine million, eight hundred forty thousand, six hundred thirty-six".