129739638 has 64 divisors (see below), whose sum is σ = 313712640. Its totient is φ = 34942752.

The previous prime is 129739633. The next prime is 129739663. The reversal of 129739638 is 836937921.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129739633) 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 31 ways as a sum of consecutive naturals, for example, 292645 + ... + 293087.

It is an arithmetic number, because the mean of its divisors is an integer number (4901760).

Almost surely, 2^129739638 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129739638, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156856320).

129739638 is an abundant number, since it is smaller than the sum of its proper divisors (183973002).

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

129739638 is a wasteful number, since it uses less digits than its factorization.

129739638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841.

The product of its digits is 489888, while the sum is 48.

The square root of 129739638 is about 11390.3308994954. The cubic root of 129739638 is about 506.2412858735.

The spelling of 129739638 in words is "one hundred twenty-nine million, seven hundred thirty-nine thousand, six hundred thirty-eight".