205111601 has 2 divisors, whose sum is σ = 205111602. Its totient is φ = 205111600.

The previous prime is 205111583. The next prime is 205111633. The reversal of 205111601 is 106111502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 196672576 + 8439025 = 14024^2 + 2905^2 .

It is a cyclic number.

It is not a de Polignac number, because 205111601 - 2¹⁴ = 205095217 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205111601.

It is not a weakly prime, because it can be changed into another prime (205111651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102555800 + 102555801.

It is an arithmetic number, because the mean of its divisors is an integer number (102555801).

Almost surely, 2^205111601 is an apocalyptic number.

It is an amenable number.

205111601 is a deficient number, since it is larger than the sum of its proper divisors (1).

205111601 is an equidigital number, since it uses as much as digits as its factorization.

205111601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 60, while the sum is 17.

The square root of 205111601 is about 14321.7178089781. The cubic root of 205111601 is about 589.7438330621.

Subtracting from 205111601 its reverse (106111502), we obtain a palindrome (99000099).

The spelling of 205111601 in words is "two hundred five million, one hundred eleven thousand, six hundred one".