206650921 has 2 divisors, whose sum is σ = 206650922. Its totient is φ = 206650920.

The previous prime is 206650907. The next prime is 206650979. The reversal of 206650921 is 129056602.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 109411600 + 97239321 = 10460^2 + 9861^2 .

It is a cyclic number.

It is not a de Polignac number, because 206650921 - 2¹¹ = 206648873 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (206650901) 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, 103325460 + 103325461.

It is an arithmetic number, because the mean of its divisors is an integer number (103325461).

Almost surely, 2^206650921 is an apocalyptic number.

It is an amenable number.

206650921 is a deficient number, since it is larger than the sum of its proper divisors (1).

206650921 is an equidigital number, since it uses as much as digits as its factorization.

206650921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 206650921 is about 14375.3581172783. The cubic root of 206650921 is about 591.2154594557.

The spelling of 206650921 in words is "two hundred six million, six hundred fifty thousand, nine hundred twenty-one".