129849960409 has 27 divisors (see below), whose sum is σ = 143584314237. Its totient is φ = 117375107616.

The previous prime is 129849960287. The next prime is 129849960479. The reversal of 129849960409 is 904069948921.

The square root of 129849960409 is 360347.

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

It can be written as a sum of positive squares in 4 ways, for example, as 3370150809 + 126479809600 = 58053^2 + 355640^2 .

It is not a de Polignac number, because 129849960409 - 2²³ = 129841571801 is a prime.

It is a super-2 number, since 2×129849960409² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (129849960479) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 248278822 + ... + 248279344.

Almost surely, 2^129849960409 is an apocalyptic number.

129849960409 is the 360347-th square number.

129849960409 is the 180174-th centered octagonal number.

It is an amenable number.

129849960409 is a deficient number, since it is larger than the sum of its proper divisors (13734353828).

129849960409 is an frugal number, since it uses more digits than its factorization.

129849960409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1178 (or 589 counting only the distinct ones).

The product of its (nonzero) digits is 10077696, while the sum is 61.

The spelling of 129849960409 in words is "one hundred twenty-nine billion, eight hundred forty-nine million, nine hundred sixty thousand, four hundred nine".