129171235216 has 45 divisors (see below), whose sum is σ = 264190467681. Its totient is φ = 61173436032.

The previous prime is 129171235199. The next prime is 129171235217. The reversal of 129171235216 is 612532171921.

The square root of 129171235216 is 359404.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2662972816 + 126508262400 = 51604^2 + 355680^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (129171235217) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 27312340 + ... + 27317068.

Almost surely, 2^129171235216 is an apocalyptic number.

129171235216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

129171235216 is the 359404-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 129171235216

129171235216 is an abundant number, since it is smaller than the sum of its proper divisors (135019232465).

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

129171235216 is an frugal number, since it uses more digits than its factorization.

129171235216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9504 (or 4750 counting only the distinct ones).

The product of its digits is 45360, while the sum is 40.

The spelling of 129171235216 in words is "one hundred twenty-nine billion, one hundred seventy-one million, two hundred thirty-five thousand, two hundred sixteen".