135943561 has 8 divisors (see below), whose sum is σ = 151449480. Its totient is φ = 121158912.

The previous prime is 135943559. The next prime is 135943609. The reversal of 135943561 is 165349531.

135943561 = 8244² + 8245².

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 81225 + 135862336 = 285^2 + 11656^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 135943561 - 2¹ = 135943559 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 135943561.

It is not an unprimeable number, because it can be changed into a prime (135943261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 179920 + ... + 180673.

It is an arithmetic number, because the mean of its divisors is an integer number (18931185).

Almost surely, 2^135943561 is an apocalyptic number.

135943561 is the 8245-th centered square number.

It is an amenable number.

135943561 is a deficient number, since it is larger than the sum of its proper divisors (15505919).

135943561 is a wasteful number, since it uses less digits than its factorization.

135943561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 360635.

The product of its digits is 48600, while the sum is 37.

The square root of 135943561 is about 11659.4837364268. The cubic root of 135943561 is about 514.1851707586.

The spelling of 135943561 in words is "one hundred thirty-five million, nine hundred forty-three thousand, five hundred sixty-one".