206117081 has 2 divisors, whose sum is σ = 206117082. Its totient is φ = 206117080.

The previous prime is 206117069. The next prime is 206117089. The reversal of 206117081 is 180711602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 121771225 + 84345856 = 11035^2 + 9184^2 .

It is a cyclic number.

It is not a de Polignac number, because 206117081 - 2¹⁸ = 205854937 is a prime.

It is a super-2 number, since 2×206117081² = 84968502159921122, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 206117081.

It is not a weakly prime, because it can be changed into another prime (206117089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103058540 + 103058541.

It is an arithmetic number, because the mean of its divisors is an integer number (103058541).

Almost surely, 2^206117081 is an apocalyptic number.

It is an amenable number.

206117081 is a deficient number, since it is larger than the sum of its proper divisors (1).

206117081 is an equidigital number, since it uses as much as digits as its factorization.

206117081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 672, while the sum is 26.

The square root of 206117081 is about 14356.7782249361. The cubic root of 206117081 is about 590.7059260761.

Adding to 206117081 its reverse (180711602), we get a palindrome (386828683).

The spelling of 206117081 in words is "two hundred six million, one hundred seventeen thousand, eighty-one".