163686561 has 16 divisors (see below), whose sum is σ = 231143424. Its totient is φ = 102819024.

The previous prime is 163686547. The next prime is 163686599. The reversal of 163686561 is 165686361.

It is not a de Polignac number, because 163686561 - 2⁵ = 163686529 is a prime.

It is not an unprimeable number, because it can be changed into a prime (163686511) 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 15 ways as a sum of consecutive naturals, for example, 13081 + ... + 22326.

It is an arithmetic number, because the mean of its divisors is an integer number (14446464).

Almost surely, 2^163686561 is an apocalyptic number.

It is an amenable number.

163686561 is a deficient number, since it is larger than the sum of its proper divisors (67456863).

163686561 is a wasteful number, since it uses less digits than its factorization.

163686561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35500.

The product of its digits is 155520, while the sum is 42.

The square root of 163686561 is about 12794.0048851015. The cubic root of 163686561 is about 547.0214312251.

The spelling of 163686561 in words is "one hundred sixty-three million, six hundred eighty-six thousand, five hundred sixty-one".