165665511101 has 2 divisors, whose sum is σ = 165665511102. Its totient is φ = 165665511100.

The previous prime is 165665511091. The next prime is 165665511149. The reversal of 165665511101 is 101115566561.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154535472100 + 11130039001 = 393110^2 + 105499^2 .

It is an emirp because it is prime and its reverse (101115566561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 165665511101 - 2³⁴ = 148485641917 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (165665511181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82832755550 + 82832755551.

It is an arithmetic number, because the mean of its divisors is an integer number (82832755551).

Almost surely, 2^165665511101 is an apocalyptic number.

It is an amenable number.

165665511101 is a deficient number, since it is larger than the sum of its proper divisors (1).

165665511101 is an equidigital number, since it uses as much as digits as its factorization.

165665511101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 27000, while the sum is 38.

The spelling of 165665511101 in words is "one hundred sixty-five billion, six hundred sixty-five million, five hundred eleven thousand, one hundred one".