129591281 has 2 divisors, whose sum is σ = 129591282. Its totient is φ = 129591280.

The previous prime is 129591257. The next prime is 129591311. The reversal of 129591281 is 182195921.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 65351056 + 64240225 = 8084^2 + 8015^2 .

It is a cyclic number.

It is not a de Polignac number, because 129591281 - 2¹⁴ = 129574897 is a prime.

It is a super-2 number, since 2×129591281² = 33587800222441922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (129591211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64795640 + 64795641.

It is an arithmetic number, because the mean of its divisors is an integer number (64795641).

Almost surely, 2^129591281 is an apocalyptic number.

It is an amenable number.

129591281 is a deficient number, since it is larger than the sum of its proper divisors (1).

129591281 is an equidigital number, since it uses as much as digits as its factorization.

129591281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12960, while the sum is 38.

The square root of 129591281 is about 11383.8166271247. The cubic root of 129591281 is about 506.0482503318.

The spelling of 129591281 in words is "one hundred twenty-nine million, five hundred ninety-one thousand, two hundred eighty-one".