205146181 has 2 divisors, whose sum is σ = 205146182. Its totient is φ = 205146180.

The previous prime is 205146121. The next prime is 205146197. The reversal of 205146181 is 181641502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 147841281 + 57304900 = 12159^2 + 7570^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205146181 is a prime.

It is a super-2 number, since 2×205146181² = 84169911157769522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205146101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102573090 + 102573091.

It is an arithmetic number, because the mean of its divisors is an integer number (102573091).

Almost surely, 2^205146181 is an apocalyptic number.

It is an amenable number.

205146181 is a deficient number, since it is larger than the sum of its proper divisors (1).

205146181 is an equidigital number, since it uses as much as digits as its factorization.

205146181 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 205146181 is about 14322.9250155127. The cubic root of 205146181 is about 589.7769730628.

Adding to 205146181 its reverse (181641502), we get a palindrome (386787683).

The spelling of 205146181 in words is "two hundred five million, one hundred forty-six thousand, one hundred eighty-one".