205131869 has 2 divisors, whose sum is σ = 205131870. Its totient is φ = 205131868.

The previous prime is 205131863. The next prime is 205131977. The reversal of 205131869 is 968131502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 180579844 + 24552025 = 13438^2 + 4955^2 .

It is a cyclic number.

It is not a de Polignac number, because 205131869 - 2⁴ = 205131853 is a prime.

It is a super-2 number, since 2×205131869² = 84158167358866322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205131863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102565934 + 102565935.

It is an arithmetic number, because the mean of its divisors is an integer number (102565935).

Almost surely, 2^205131869 is an apocalyptic number.

It is an amenable number.

205131869 is a deficient number, since it is larger than the sum of its proper divisors (1).

205131869 is an equidigital number, since it uses as much as digits as its factorization.

205131869 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12960, while the sum is 35.

The square root of 205131869 is about 14322.4253881806. The cubic root of 205131869 is about 589.7632575027.

The spelling of 205131869 in words is "two hundred five million, one hundred thirty-one thousand, eight hundred sixty-nine".