129170000 has 50 divisors (see below), whose sum is σ = 312757698. Its totient is φ = 51664000.

The previous prime is 129169987. The next prime is 129170003. The reversal of 129170000 is 71921.

It can be written as a sum of positive squares in 5 ways, for example, as 47665216 + 81504784 = 6904^2 + 9028^2 .

It is a tau number, because it is divible by the number of its divisors (50).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129170003) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 3542 + ... + 16458.

Almost surely, 2^129170000 is an apocalyptic number.

129170000 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 129170000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (156378849).

129170000 is an abundant number, since it is smaller than the sum of its proper divisors (183587698).

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

129170000 is an equidigital number, since it uses as much as digits as its factorization.

129170000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12945 (or 12924 counting only the distinct ones).

The product of its (nonzero) digits is 126, while the sum is 20.

The square root of 129170000 is about 11365.2980603238. The cubic root of 129170000 is about 505.4992937878.

The spelling of 129170000 in words is "one hundred twenty-nine million, one hundred seventy thousand".