129671896720 has 20 divisors (see below), whose sum is σ = 301487160060. Its totient is φ = 51868758656.

The previous prime is 129671896699. The next prime is 129671896729. The reversal of 129671896720 is 27698176921.

It can be written as a sum of positive squares in 2 ways, for example, as 53542257664 + 76129639056 = 231392^2 + 275916^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is not an unprimeable number, because it can be changed into a prime (129671896729) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 810449275 + ... + 810449434.

It is an arithmetic number, because the mean of its divisors is an integer number (15074358003).

Almost surely, 2^129671896720 is an apocalyptic number.

129671896720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129671896720 is an abundant number, since it is smaller than the sum of its proper divisors (171815263340).

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

129671896720 is a wasteful number, since it uses less digits than its factorization.

129671896720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1620898722 (or 1620898716 counting only the distinct ones).

The product of its (nonzero) digits is 4572288, while the sum is 58.

The spelling of 129671896720 in words is "one hundred twenty-nine billion, six hundred seventy-one million, eight hundred ninety-six thousand, seven hundred twenty".