205663897 has 2 divisors, whose sum is σ = 205663898. Its totient is φ = 205663896.

The previous prime is 205663891. The next prime is 205663921. The reversal of 205663897 is 798366502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 182277001 + 23386896 = 13501^2 + 4836^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205663897 is a prime.

It is not a weakly prime, because it can be changed into another prime (205663891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102831948 + 102831949.

It is an arithmetic number, because the mean of its divisors is an integer number (102831949).

Almost surely, 2^205663897 is an apocalyptic number.

It is an amenable number.

205663897 is a deficient number, since it is larger than the sum of its proper divisors (1).

205663897 is an equidigital number, since it uses as much as digits as its factorization.

205663897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 544320, while the sum is 46.

The square root of 205663897 is about 14340.9866118060. The cubic root of 205663897 is about 590.2726854039.

The spelling of 205663897 in words is "two hundred five million, six hundred sixty-three thousand, eight hundred ninety-seven".