201663365609 has 2 divisors, whose sum is σ = 201663365610. Its totient is φ = 201663365608.

The previous prime is 201663365551. The next prime is 201663365633. The reversal of 201663365609 is 906563366102.

201663365609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 145768949209 + 55894416400 = 381797^2 + 236420^2 .

It is a cyclic number.

It is not a de Polignac number, because 201663365609 - 2²⁰ = 201662317033 is a prime.

It is a super-2 number, since 2×201663365609² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (201663325609) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100831682804 + 100831682805.

It is an arithmetic number, because the mean of its divisors is an integer number (100831682805).

Almost surely, 2^201663365609 is an apocalyptic number.

It is an amenable number.

201663365609 is a deficient number, since it is larger than the sum of its proper divisors (1).

201663365609 is an equidigital number, since it uses as much as digits as its factorization.

201663365609 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1049760, while the sum is 47.

The spelling of 201663365609 in words is "two hundred one billion, six hundred sixty-three million, three hundred sixty-five thousand, six hundred nine".