129281 has 2 divisors, whose sum is σ = 129282. Its totient is φ = 129280.

The previous prime is 129277. The next prime is 129287. The reversal of 129281 is 182921.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 128881 + 400 = 359^2 + 20^2 .

It is an emirp because it is prime and its reverse (182921) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 129281 - 2² = 129277 is a prime.

It is a super-2 number, since 2×129281² = 33427153922, which contains 22 as substring.

It is a Sophie Germain prime.

It is an Ulam number.

It is a Curzon number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 129281.

It is not a weakly prime, because it can be changed into another prime (129287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64640 + 64641.

It is an arithmetic number, because the mean of its divisors is an integer number (64641).

2¹²⁹²⁸¹ is an apocalyptic number.

It is an amenable number.

129281 is a deficient number, since it is larger than the sum of its proper divisors (1).

129281 is an equidigital number, since it uses as much as digits as its factorization.

129281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 288, while the sum is 23.

The square root of 129281 is about 359.5566714720. The cubic root of 129281 is about 50.5644049683.

The spelling of 129281 in words is "one hundred twenty-nine thousand, two hundred eighty-one".