205519969 has 2 divisors, whose sum is σ = 205519970. Its totient is φ = 205519968.

The previous prime is 205519939. The next prime is 205519997. The reversal of 205519969 is 969915502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111197025 + 94322944 = 10545^2 + 9712^2 .

It is a cyclic number.

It is not a de Polignac number, because 205519969 - 2⁷ = 205519841 is a prime.

It is a super-2 number, since 2×205519969² = 84476915315521922, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (205519939) 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, 102759984 + 102759985.

It is an arithmetic number, because the mean of its divisors is an integer number (102759985).

Almost surely, 2^205519969 is an apocalyptic number.

It is an amenable number.

205519969 is a deficient number, since it is larger than the sum of its proper divisors (1).

205519969 is an equidigital number, since it uses as much as digits as its factorization.

205519969 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 218700, while the sum is 46.

The square root of 205519969 is about 14335.9676687693. The cubic root of 205519969 is about 590.1349581148.

The spelling of 205519969 in words is "two hundred five million, five hundred nineteen thousand, nine hundred sixty-nine".