129090 has 32 divisors (see below), whose sum is σ = 334656. Its totient is φ = 31680.

The previous prime is 129089. The next prime is 129097. The reversal of 129090 is 90921.

It is a happy number.

It is a Smith number, since the sum of its digits (21) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129097) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 225 + ... + 555.

It is an arithmetic number, because the mean of its divisors is an integer number (10458).

2¹²⁹⁰⁹⁰ is an apocalyptic number.

129090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 129090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (167328).

129090 is an abundant number, since it is smaller than the sum of its proper divisors (205566).

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

129090 is a wasteful number, since it uses less digits than its factorization.

129090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354.

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

The square root of 129090 is about 359.2909684364. The cubic root of 129090 is about 50.5394913785.

The spelling of 129090 in words is "one hundred twenty-nine thousand, ninety".