135608261 has 4 divisors (see below), whose sum is σ = 136584000. Its totient is φ = 134632524.

The previous prime is 135608251. The next prime is 135608267. The reversal of 135608261 is 162806531.

It is a happy number.

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 135608261 - 2¹⁸ = 135346117 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 (135608267) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 487661 + ... + 487938.

It is an arithmetic number, because the mean of its divisors is an integer number (34146000).

Almost surely, 2^135608261 is an apocalyptic number.

It is an amenable number.

135608261 is a deficient number, since it is larger than the sum of its proper divisors (975739).

135608261 is an equidigital number, since it uses as much as digits as its factorization.

135608261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 975738.

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 135608261 is about 11645.0960064741. The cubic root of 135608261 is about 513.7620828592.

The spelling of 135608261 in words is "one hundred thirty-five million, six hundred eight thousand, two hundred sixty-one".