129516666320 has 20 divisors (see below), whose sum is σ = 301126249380. Its totient is φ = 51806666496.

The previous prime is 129516666313. The next prime is 129516666337. The reversal of 129516666320 is 23666615921.

It can be written as a sum of positive squares in 2 ways, for example, as 57136297024 + 72380369296 = 239032^2 + 269036^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 809479085 + ... + 809479244.

It is an arithmetic number, because the mean of its divisors is an integer number (15056312469).

Almost surely, 2^129516666320 is an apocalyptic number.

129516666320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

129516666320 is an abundant number, since it is smaller than the sum of its proper divisors (171609583060).

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

129516666320 is a wasteful number, since it uses less digits than its factorization.

129516666320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1618958342 (or 1618958336 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 47.

The spelling of 129516666320 in words is "one hundred twenty-nine billion, five hundred sixteen million, six hundred sixty-six thousand, three hundred twenty".