205102861 has 2 divisors, whose sum is σ = 205102862. Its totient is φ = 205102860.

The previous prime is 205102831. The next prime is 205102871. The reversal of 205102861 is 168201502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 153908836 + 51194025 = 12406^2 + 7155^2 .

It is a cyclic number.

It is not a de Polignac number, because 205102861 - 2¹⁹ = 204578573 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205102811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102551430 + 102551431.

It is an arithmetic number, because the mean of its divisors is an integer number (102551431).

Almost surely, 2^205102861 is an apocalyptic number.

It is an amenable number.

205102861 is a deficient number, since it is larger than the sum of its proper divisors (1).

205102861 is an equidigital number, since it uses as much as digits as its factorization.

205102861 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 960, while the sum is 25.

The square root of 205102861 is about 14321.4126747329. The cubic root of 205102861 is about 589.7354564283.

The spelling of 205102861 in words is "two hundred five million, one hundred two thousand, eight hundred sixty-one".