129260640 has 96 divisors (see below), whose sum is σ = 414935136. Its totient is φ = 33812480.

The previous prime is 129260633. The next prime is 129260641. The reversal of 129260640 is 46062921.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 129260598 and 129260607.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129260641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22900 + ... + 27980.

It is an arithmetic number, because the mean of its divisors is an integer number (4322241).

Almost surely, 2^129260640 is an apocalyptic number.

129260640 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 129260640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (207467568).

129260640 is an abundant number, since it is smaller than the sum of its proper divisors (285674496).

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

129260640 is a wasteful number, since it uses less digits than its factorization.

129260640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5152 (or 5144 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 30.

The square root of 129260640 is about 11369.2849379370. The cubic root of 129260640 is about 505.6175042677.

The spelling of 129260640 in words is "one hundred twenty-nine million, two hundred sixty thousand, six hundred forty".