205321531 has 2 divisors, whose sum is σ = 205321532. Its totient is φ = 205321530.

The previous prime is 205321511. The next prime is 205321559. The reversal of 205321531 is 135123502.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 205321531 - 2¹¹ = 205319483 is a prime.

It is a super-2 number, since 2×205321531² = 84313862184367922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (205321511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102660765 + 102660766.

It is an arithmetic number, because the mean of its divisors is an integer number (102660766).

Almost surely, 2^205321531 is an apocalyptic number.

205321531 is a deficient number, since it is larger than the sum of its proper divisors (1).

205321531 is an equidigital number, since it uses as much as digits as its factorization.

205321531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 205321531 is about 14329.0450135381. The cubic root of 205321531 is about 589.9449637450.

The spelling of 205321531 in words is "two hundred five million, three hundred twenty-one thousand, five hundred thirty-one".