129240 has 48 divisors (see below), whose sum is σ = 421200. Its totient is φ = 34368.

The previous prime is 129229. The next prime is 129263. The reversal of 129240 is 42921.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 181 + ... + 539.

It is an arithmetic number, because the mean of its divisors is an integer number (8775).

2¹²⁹²⁴⁰ is an apocalyptic number.

129240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a pronic number, being equal to 359×360.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210600).

129240 is an abundant number, since it is smaller than the sum of its proper divisors (291960).

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

129240 is a wasteful number, since it uses less digits than its factorization.

129240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 376 (or 369 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 129240 is about 359.4996522947. The cubic root of 129240 is about 50.5590590943.

It can be divided in two parts, 1 and 29240, that added together give a square (29241 = 171²).

The spelling of 129240 in words is "one hundred twenty-nine thousand, two hundred forty".