135128317 has 4 divisors (see below), whose sum is σ = 138270880. Its totient is φ = 131985756.

The previous prime is 135128311. The next prime is 135128321. The reversal of 135128317 is 713821531.

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 a de Polignac number, because none of the positive numbers 2^k-135128317 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135128311) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1571217 + ... + 1571302.

It is an arithmetic number, because the mean of its divisors is an integer number (34567720).

Almost surely, 2^135128317 is an apocalyptic number.

It is an amenable number.

135128317 is a deficient number, since it is larger than the sum of its proper divisors (3142563).

135128317 is an equidigital number, since it uses as much as digits as its factorization.

135128317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3142562.

The product of its digits is 5040, while the sum is 31.

The square root of 135128317 is about 11624.4706116021. The cubic root of 135128317 is about 513.1552651151.

Adding to 135128317 its reverse (713821531), we get a palindrome (848949848).

The spelling of 135128317 in words is "one hundred thirty-five million, one hundred twenty-eight thousand, three hundred seventeen".