206684939 has 2 divisors, whose sum is σ = 206684940. Its totient is φ = 206684938.

The previous prime is 206684911. The next prime is 206684941. The reversal of 206684939 is 939486602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-206684939 is a prime.

Together with 206684941, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 206684893 and 206684902.

It is not a weakly prime, because it can be changed into another prime (206684909) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103342469 + 103342470.

It is an arithmetic number, because the mean of its divisors is an integer number (103342470).

Almost surely, 2^206684939 is an apocalyptic number.

206684939 is a deficient number, since it is larger than the sum of its proper divisors (1).

206684939 is an equidigital number, since it uses as much as digits as its factorization.

206684939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 559872, while the sum is 47.

The square root of 206684939 is about 14376.5412738948. The cubic root of 206684939 is about 591.2478988046.

The spelling of 206684939 in words is "two hundred six million, six hundred eighty-four thousand, nine hundred thirty-nine".