205820623 has 2 divisors, whose sum is σ = 205820624. Its totient is φ = 205820622.

The previous prime is 205820611. The next prime is 205820639. The reversal of 205820623 is 326028502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205820623 - 2¹⁷ = 205689551 is a prime.

It is equal to p_11383273 and since 205820623 and 11383273 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 205820591 and 205820600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205820723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102910311 + 102910312.

It is an arithmetic number, because the mean of its divisors is an integer number (102910312).

Almost surely, 2^205820623 is an apocalyptic number.

205820623 is the 7669-th centered heptagonal number.

205820623 is a deficient number, since it is larger than the sum of its proper divisors (1).

205820623 is an equidigital number, since it uses as much as digits as its factorization.

205820623 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5760, while the sum is 28.

The square root of 205820623 is about 14346.4498395945. The cubic root of 205820623 is about 590.4225862678.

The spelling of 205820623 in words is "two hundred five million, eight hundred twenty thousand, six hundred twenty-three".