208861811 has 2 divisors, whose sum is σ = 208861812. Its totient is φ = 208861810.

The previous prime is 208861801. The next prime is 208861819. The reversal of 208861811 is 118168802.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208861811 is a prime.

It is a super-3 number, since 3×208861811³ (a number of 26 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (208861819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104430905 + 104430906.

It is an arithmetic number, because the mean of its divisors is an integer number (104430906).

Almost surely, 2^208861811 is an apocalyptic number.

208861811 is a deficient number, since it is larger than the sum of its proper divisors (1).

208861811 is an equidigital number, since it uses as much as digits as its factorization.

208861811 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6144, while the sum is 35.

The square root of 208861811 is about 14452.0521380183. The cubic root of 208861811 is about 593.3163911405.

The spelling of 208861811 in words is "two hundred eight million, eight hundred sixty-one thousand, eight hundred eleven".