135488581 has 4 divisors (see below), whose sum is σ = 135739564. Its totient is φ = 135237600.

The previous prime is 135488489. The next prime is 135488597. The reversal of 135488581 is 185884531.

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 105884100 + 29604481 = 10290^2 + 5441^2 .

It is a cyclic number.

It is not a de Polignac number, because 135488581 - 2¹⁹ = 134964293 is a prime.

It is a super-2 number, since 2×135488581² = 36714311162787122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135480581) 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, 124680 + ... + 125761.

It is an arithmetic number, because the mean of its divisors is an integer number (33934891).

Almost surely, 2^135488581 is an apocalyptic number.

It is an amenable number.

135488581 is a deficient number, since it is larger than the sum of its proper divisors (250983).

135488581 is an equidigital number, since it uses as much as digits as its factorization.

135488581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250982.

The product of its digits is 153600, while the sum is 43.

The square root of 135488581 is about 11639.9562284400. The cubic root of 135488581 is about 513.6108994854.

The spelling of 135488581 in words is "one hundred thirty-five million, four hundred eighty-eight thousand, five hundred eighty-one".