205665137 has 2 divisors, whose sum is σ = 205665138. Its totient is φ = 205665136.

The previous prime is 205665127. The next prime is 205665151. The reversal of 205665137 is 731566502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 187991521 + 17673616 = 13711^2 + 4204^2 .

It is a cyclic number.

It is not a de Polignac number, because 205665137 - 2⁴ = 205665121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 205665097 and 205665106.

It is not a weakly prime, because it can be changed into another prime (205665127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102832568 + 102832569.

It is an arithmetic number, because the mean of its divisors is an integer number (102832569).

Almost surely, 2^205665137 is an apocalyptic number.

It is an amenable number.

205665137 is a deficient number, since it is larger than the sum of its proper divisors (1).

205665137 is an equidigital number, since it uses as much as digits as its factorization.

205665137 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 37800, while the sum is 35.

The square root of 205665137 is about 14341.0298444707. The cubic root of 205665137 is about 590.2738717029.

The spelling of 205665137 in words is "two hundred five million, six hundred sixty-five thousand, one hundred thirty-seven".