129708244520 has 128 divisors (see below), whose sum is σ = 311051059200. Its totient is φ = 48596889600.

The previous prime is 129708244517. The next prime is 129708244531. The reversal of 129708244520 is 25442807921.

It is a super-2 number, since 2×129708244520² (a number of 23 digits) contains 22 as substring.

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, 6446636 + ... + 6466724.

It is an arithmetic number, because the mean of its divisors is an integer number (2430086400).

Almost surely, 2^129708244520 is an apocalyptic number.

129708244520 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 129708244520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (155525529600).

129708244520 is an abundant number, since it is smaller than the sum of its proper divisors (181342814680).

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

129708244520 is a wasteful number, since it uses less digits than its factorization.

129708244520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20299 (or 20295 counting only the distinct ones).

The product of its (nonzero) digits is 322560, while the sum is 44.

The spelling of 129708244520 in words is "one hundred twenty-nine billion, seven hundred eight million, two hundred forty-four thousand, five hundred twenty".