135320321 has 4 divisors (see below), whose sum is σ = 135365700. Its totient is φ = 135274944.

The previous prime is 135320291. The next prime is 135320333. The reversal of 135320321 is 123023531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 123023531 = 31 ⋅3968501.

It can be written as a sum of positive squares in 2 ways, for example, as 112890625 + 22429696 = 10625^2 + 4736^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135320321 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 135320293 and 135320302.

It is not an unprimeable number, because it can be changed into a prime (135320371) 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, 17876 + ... + 24293.

It is an arithmetic number, because the mean of its divisors is an integer number (33841425).

Almost surely, 2^135320321 is an apocalyptic number.

It is an amenable number.

135320321 is a deficient number, since it is larger than the sum of its proper divisors (45379).

135320321 is an equidigital number, since it uses as much as digits as its factorization.

135320321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45378.

The product of its (nonzero) digits is 540, while the sum is 20.

The square root of 135320321 is about 11632.7262926624. The cubic root of 135320321 is about 513.3981977497.

Adding to 135320321 its reverse (123023531), we get a palindrome (258343852).

The spelling of 135320321 in words is "one hundred thirty-five million, three hundred twenty thousand, three hundred twenty-one".