206861771 has 2 divisors, whose sum is σ = 206861772. Its totient is φ = 206861770.

The previous prime is 206861749. The next prime is 206861773. The reversal of 206861771 is 177168602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206861771 is a prime.

Together with 206861773, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (206861773) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103430885 + 103430886.

It is an arithmetic number, because the mean of its divisors is an integer number (103430886).

Almost surely, 2^206861771 is an apocalyptic number.

206861771 is a deficient number, since it is larger than the sum of its proper divisors (1).

206861771 is an equidigital number, since it uses as much as digits as its factorization.

206861771 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 28224, while the sum is 38.

The square root of 206861771 is about 14382.6899778866. The cubic root of 206861771 is about 591.4164673617.

The spelling of 206861771 in words is "two hundred six million, eight hundred sixty-one thousand, seven hundred seventy-one".