135806561 has 8 divisors (see below), whose sum is σ = 149320704. Its totient is φ = 122487120.

The previous prime is 135806551. The next prime is 135806579. The reversal of 135806561 is 165608531.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135806561 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (135806551) 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, 47210 + ... + 50003.

It is an arithmetic number, because the mean of its divisors is an integer number (18665088).

Almost surely, 2^135806561 is an apocalyptic number.

135806561 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

135806561 is a deficient number, since it is larger than the sum of its proper divisors (13514143).

135806561 is a wasteful number, since it uses less digits than its factorization.

135806561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97351.

The product of its (nonzero) digits is 21600, while the sum is 35.

The square root of 135806561 is about 11653.6072097870. The cubic root of 135806561 is about 514.0123857079.

The spelling of 135806561 in words is "one hundred thirty-five million, eight hundred six thousand, five hundred sixty-one".