206678957 has 2 divisors, whose sum is σ = 206678958. Its totient is φ = 206678956.

The previous prime is 206678917. The next prime is 206678981. The reversal of 206678957 is 759876602.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206611876 + 67081 = 14374^2 + 259^2 .

It is a cyclic number.

It is not a de Polignac number, because 206678957 - 2⁸ = 206678701 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (206678917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 103339478 + 103339479.

It is an arithmetic number, because the mean of its divisors is an integer number (103339479).

Almost surely, 2^206678957 is an apocalyptic number.

It is an amenable number.

206678957 is a deficient number, since it is larger than the sum of its proper divisors (1).

206678957 is an equidigital number, since it uses as much as digits as its factorization.

206678957 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1270080, while the sum is 50.

The square root of 206678957 is about 14376.3332251308. Note that the first 3 decimals coincide. The cubic root of 206678957 is about 591.2421946653.

The spelling of 206678957 in words is "two hundred six million, six hundred seventy-eight thousand, nine hundred fifty-seven".