135610661 has 4 divisors (see below), whose sum is σ = 139275852. Its totient is φ = 131945472.

The previous prime is 135610627. The next prime is 135610669. The reversal of 135610661 is 166016531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 166016531 = 71 ⋅2338261.

It can be written as a sum of positive squares in 2 ways, for example, as 129390625 + 6220036 = 11375^2 + 2494^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135610661 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 (135610669) 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, 1832540 + ... + 1832613.

It is an arithmetic number, because the mean of its divisors is an integer number (34818963).

Almost surely, 2^135610661 is an apocalyptic number.

It is an amenable number.

135610661 is a deficient number, since it is larger than the sum of its proper divisors (3665191).

135610661 is an equidigital number, since it uses as much as digits as its factorization.

135610661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3665190.

The product of its (nonzero) digits is 3240, while the sum is 29.

The square root of 135610661 is about 11645.1990536873. The cubic root of 135610661 is about 513.7651137014.

The spelling of 135610661 in words is "one hundred thirty-five million, six hundred ten thousand, six hundred sixty-one".