206710681 has 2 divisors, whose sum is σ = 206710682. Its totient is φ = 206710680.

The previous prime is 206710663. The next prime is 206710703. The reversal of 206710681 is 186017602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 200505600 + 6205081 = 14160^2 + 2491^2 .

It is a cyclic number.

It is not a de Polignac number, because 206710681 - 2⁹ = 206710169 is a prime.

It is a super-2 number, since 2×206710681² = 85458611278967522, which contains 22 as substring.

It is equal to p_11429734 and since 206710681 and 11429734 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (206710381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103355340 + 103355341.

It is an arithmetic number, because the mean of its divisors is an integer number (103355341).

Almost surely, 2^206710681 is an apocalyptic number.

It is an amenable number.

206710681 is a deficient number, since it is larger than the sum of its proper divisors (1).

206710681 is an equidigital number, since it uses as much as digits as its factorization.

206710681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 206710681 is about 14377.4365239426. The cubic root of 206710681 is about 591.2724438467.

The spelling of 206710681 in words is "two hundred six million, seven hundred ten thousand, six hundred eighty-one".