165611 has 2 divisors, whose sum is σ = 165612. Its totient is φ = 165610.

The previous prime is 165601. The next prime is 165617. The reversal of 165611 is 116561.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 165611 - 2¹⁰ = 164587 is a prime.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 165611.

It is not a weakly prime, because it can be changed into another prime (165617) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82805 + 82806.

It is an arithmetic number, because the mean of its divisors is an integer number (82806).

2¹⁶⁵⁶¹¹ is an apocalyptic number.

165611 is a deficient number, since it is larger than the sum of its proper divisors (1).

165611 is an equidigital number, since it uses as much as digits as its factorization.

165611 is an evil number, because the sum of its binary digits is even.

The product of its digits is 180, while the sum is 20.

The square root of 165611 is about 406.9533142757. The cubic root of 165611 is about 54.9156834787.

The spelling of 165611 in words is "one hundred sixty-five thousand, six hundred eleven".