165727561 has 8 divisors (see below), whose sum is σ = 168441984. Its totient is φ = 163023840.

The previous prime is 165727469. The next prime is 165727571.

It is a happy number.

165727561 is nontrivially palindromic in base 10.

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 165727561 - 2⁷ = 165727433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (165727571) 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 7 ways as a sum of consecutive naturals, for example, 32181 + ... + 36973.

It is an arithmetic number, because the mean of its divisors is an integer number (21055248).

Almost surely, 2^165727561 is an apocalyptic number.

It is an amenable number.

165727561 is a deficient number, since it is larger than the sum of its proper divisors (2714423).

165727561 is an equidigital number, since it uses as much as digits as its factorization.

165727561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5351.

The product of its digits is 88200, while the sum is 40.

The square root of 165727561 is about 12873.5217015392. The cubic root of 165727561 is about 549.2856411630.

The spelling of 165727561 in words is "one hundred sixty-five million, seven hundred twenty-seven thousand, five hundred sixty-one".