129785800 has 48 divisors (see below), whose sum is σ = 308194560. Its totient is φ = 50806080.

The previous prime is 129785797. The next prime is 129785801. The reversal of 129785800 is 8587921.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (129785801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2497 + ... + 16303.

It is an arithmetic number, because the mean of its divisors is an integer number (6420720).

Almost surely, 2^129785800 is an apocalyptic number.

129785800 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 129785800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (154097280).

129785800 is an abundant number, since it is smaller than the sum of its proper divisors (178408760).

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

129785800 is a wasteful number, since it uses less digits than its factorization.

129785800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13870 (or 13861 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 129785800 is about 11392.3570871001. The cubic root of 129785800 is about 506.3013197987.

The spelling of 129785800 in words is "one hundred twenty-nine million, seven hundred eighty-five thousand, eight hundred".