129038581 has 4 divisors (see below), whose sum is σ = 147472672. Its totient is φ = 110604492.

The previous prime is 129038561. The next prime is 129038593. The reversal of 129038581 is 185830921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 129038581 - 2⁹ = 129038069 is a prime.

It is a super-2 number, since 2×129038581² = 33301910772987122, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 129038581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (129038501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9217035 + ... + 9217048.

It is an arithmetic number, because the mean of its divisors is an integer number (36868168).

Almost surely, 2^129038581 is an apocalyptic number.

It is an amenable number.

129038581 is a deficient number, since it is larger than the sum of its proper divisors (18434091).

129038581 is an equidigital number, since it uses as much as digits as its factorization.

129038581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18434090.

The product of its (nonzero) digits is 17280, while the sum is 37.

The square root of 129038581 is about 11359.5149984495. The cubic root of 129038581 is about 505.3278020739.

The spelling of 129038581 in words is "one hundred twenty-nine million, thirty-eight thousand, five hundred eighty-one".