129704820 has 192 divisors, whose sum is σ = 449003520. Its totient is φ = 27320832.

The previous prime is 129704801. The next prime is 129704821. The reversal of 129704820 is 28407921.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129704821) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 279909 + ... + 280371.

It is an arithmetic number, because the mean of its divisors is an integer number (2338560).

Almost surely, 2^129704820 is an apocalyptic number.

129704820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129704820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (224501760).

129704820 is an abundant number, since it is smaller than the sum of its proper divisors (319298700).

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

129704820 is a wasteful number, since it uses less digits than its factorization.

129704820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 534 (or 532 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 129704820 is about 11388.8023953355. The cubic root of 129704820 is about 506.1959954586.

The spelling of 129704820 in words is "one hundred twenty-nine million, seven hundred four thousand, eight hundred twenty".