205654381 has 2 divisors, whose sum is σ = 205654382. Its totient is φ = 205654380.

The previous prime is 205654373. The next prime is 205654409. The reversal of 205654381 is 183456502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 199233225 + 6421156 = 14115^2 + 2534^2 .

It is a cyclic number.

It is not a de Polignac number, because 205654381 - 2³ = 205654373 is a prime.

It is a super-2 number, since 2×205654381² = 84587448848986322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205658381) 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, 102827190 + 102827191.

It is an arithmetic number, because the mean of its divisors is an integer number (102827191).

Almost surely, 2^205654381 is an apocalyptic number.

It is an amenable number.

205654381 is a deficient number, since it is larger than the sum of its proper divisors (1).

205654381 is an equidigital number, since it uses as much as digits as its factorization.

205654381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28800, while the sum is 34.

The square root of 205654381 is about 14340.6548316316. The cubic root of 205654381 is about 590.2635813566.

The spelling of 205654381 in words is "two hundred five million, six hundred fifty-four thousand, three hundred eighty-one".