129900 has 36 divisors (see below), whose sum is σ = 376712. Its totient is φ = 34560.

The previous prime is 129893. The next prime is 129901. The reversal of 129900 is 9921.

It is a happy number.

129900 is nontrivially palindromic in base 7.

It is a nialpdrome in base 12.

It is not an unprimeable number, because it can be changed into a prime (129901) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84 + ... + 516.

2¹²⁹⁹⁰⁰ is an apocalyptic number.

129900 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 129900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188356).

129900 is an abundant number, since it is smaller than the sum of its proper divisors (246812).

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

129900 is a wasteful number, since it uses less digits than its factorization.

129900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 450 (or 443 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 21.

The square root of 129900 is about 360.4164258188. The cubic root of 129900 is about 50.6449776359.

Adding to 129900 its sum of digits (21), we get a palindrome (129921).

The spelling of 129900 in words is "one hundred twenty-nine thousand, nine hundred".