129640 has 32 divisors (see below), whose sum is σ = 334080. Its totient is φ = 44352.

The previous prime is 129631. The next prime is 129641. The reversal of 129640 is 46921.

It is not an unprimeable number, because it can be changed into a prime (129641) 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, 49 + ... + 511.

It is an arithmetic number, because the mean of its divisors is an integer number (10440).

129640 is a Friedman number, since it can be written as 926*140, using all its digits and the basic arithmetic operations.

It is a vampire number, since it can be written as 140 ⋅ 926 (with its own digits).

2¹²⁹⁶⁴⁰ is an apocalyptic number.

129640 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 129640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (167040).

129640 is an abundant number, since it is smaller than the sum of its proper divisors (204440).

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

129640 is a wasteful number, since it uses less digits than its factorization.

129640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 481 (or 477 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 129640 is about 360.0555512695. The cubic root of 129640 is about 50.6111657570.

The spelling of 129640 in words is "one hundred twenty-nine thousand, six hundred forty".