129784240 has 40 divisors (see below), whose sum is σ = 303449328. Its totient is φ = 51621120.

The previous prime is 129784219. The next prime is 129784241. The reversal of 129784240 is 42487921.

It is a tau number, because it is divible by the number of its divisors (40).

It is a plaindrome in base 14.

It is a self number, because there is not a number n which added to its sum of digits gives 129784240.

It is not an unprimeable number, because it can be changed into a prime (129784241) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9999 + ... + 18961.

Almost surely, 2^129784240 is an apocalyptic number.

129784240 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 129784240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151724664).

129784240 is an abundant number, since it is smaller than the sum of its proper divisors (173665088).

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

129784240 is a wasteful number, since it uses less digits than its factorization.

129784240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9157 (or 9151 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 129784240 is about 11392.2886199394. The cubic root of 129784240 is about 506.2992912429.

The spelling of 129784240 in words is "one hundred twenty-nine million, seven hundred eighty-four thousand, two hundred forty".