135523261 has 4 divisors (see below), whose sum is σ = 135662112. Its totient is φ = 135384412.

The previous prime is 135523247. The next prime is 135523307. The reversal of 135523261 is 162325531.

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 135523261 - 2²¹ = 133426109 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 (135523961) 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, 67951 + ... + 69916.

It is an arithmetic number, because the mean of its divisors is an integer number (33915528).

Almost surely, 2^135523261 is an apocalyptic number.

It is an amenable number.

135523261 is a deficient number, since it is larger than the sum of its proper divisors (138851).

135523261 is an equidigital number, since it uses as much as digits as its factorization.

135523261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138850.

The product of its digits is 5400, while the sum is 28.

The square root of 135523261 is about 11641.4458294492. The cubic root of 135523261 is about 513.6547174621.

Adding to 135523261 its reverse (162325531), we get a palindrome (297848792).

The spelling of 135523261 in words is "one hundred thirty-five million, five hundred twenty-three thousand, two hundred sixty-one".