205445231 has 2 divisors, whose sum is σ = 205445232. Its totient is φ = 205445230.

The previous prime is 205445209. The next prime is 205445263. The reversal of 205445231 is 132544502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205445231 is a prime.

It is a super-2 number, since 2×205445231² = 84415485881286722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 205445231.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205445431) 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, 102722615 + 102722616.

It is an arithmetic number, because the mean of its divisors is an integer number (102722616).

Almost surely, 2^205445231 is an apocalyptic number.

205445231 is a deficient number, since it is larger than the sum of its proper divisors (1).

205445231 is an equidigital number, since it uses as much as digits as its factorization.

205445231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 26.

The square root of 205445231 is about 14333.3607712916. The cubic root of 205445231 is about 590.0634146144.

Adding to 205445231 its reverse (132544502), we get a palindrome (337989733).

The spelling of 205445231 in words is "two hundred five million, four hundred forty-five thousand, two hundred thirty-one".