129944640 has 224 divisors, whose sum is σ = 480754944. Its totient is φ = 29122560.

The previous prime is 129944627. The next prime is 129944657. The reversal of 129944640 is 46449921.

It is a tau number, because it is divible by the number of its divisors (224).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 409762 + ... + 410078.

Almost surely, 2^129944640 is an apocalyptic number.

129944640 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 129944640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (240377472).

129944640 is an abundant number, since it is smaller than the sum of its proper divisors (350810304).

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

129944640 is a wasteful number, since it uses less digits than its factorization.

129944640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405 (or 395 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 129944640 is about 11399.3262958826. The cubic root of 129944640 is about 506.5077833612.

The spelling of 129944640 in words is "one hundred twenty-nine million, nine hundred forty-four thousand, six hundred forty".