205881281 has 2 divisors, whose sum is σ = 205881282. Its totient is φ = 205881280.

The previous prime is 205881259. The next prime is 205881287. The reversal of 205881281 is 182188502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 167935681 + 37945600 = 12959^2 + 6160^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205881281 is a prime.

It is a super-3 number, since 3×205881281³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (205881287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102940640 + 102940641.

It is an arithmetic number, because the mean of its divisors is an integer number (102940641).

Almost surely, 2^205881281 is an apocalyptic number.

It is an amenable number.

205881281 is a deficient number, since it is larger than the sum of its proper divisors (1).

205881281 is an equidigital number, since it uses as much as digits as its factorization.

205881281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10240, while the sum is 35.

The square root of 205881281 is about 14348.5637260320. The cubic root of 205881281 is about 590.4805822953.

The spelling of 205881281 in words is "two hundred five million, eight hundred eighty-one thousand, two hundred eighty-one".