135442655521 has 4 divisors (see below), whose sum is σ = 135450643012. Its totient is φ = 135434668032.

The previous prime is 135442655519. The next prime is 135442655549. The reversal of 135442655521 is 125556244531.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 74761230625 + 60681424896 = 273425^2 + 246336^2 .

It is a cyclic number.

It is not a de Polignac number, because 135442655521 - 2¹ = 135442655519 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (135442605521) 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, 3968256 + ... + 4002241.

It is an arithmetic number, because the mean of its divisors is an integer number (33862660753).

Almost surely, 2^135442655521 is an apocalyptic number.

It is an amenable number.

135442655521 is a deficient number, since it is larger than the sum of its proper divisors (7987491).

135442655521 is an equidigital number, since it uses as much as digits as its factorization.

135442655521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7987490.

The product of its digits is 720000, while the sum is 43.

The spelling of 135442655521 in words is "one hundred thirty-five billion, four hundred forty-two million, six hundred fifty-five thousand, five hundred twenty-one".