208218133 has 2 divisors, whose sum is σ = 208218134. Its totient is φ = 208218132.

The previous prime is 208218121. The next prime is 208218137. The reversal of 208218133 is 331812802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 196644529 + 11573604 = 14023^2 + 3402^2 .

It is a cyclic number.

It is not a de Polignac number, because 208218133 - 2¹³ = 208209941 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208218137) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104109066 + 104109067.

It is an arithmetic number, because the mean of its divisors is an integer number (104109067).

Almost surely, 2^208218133 is an apocalyptic number.

It is an amenable number.

208218133 is a deficient number, since it is larger than the sum of its proper divisors (1).

208218133 is an equidigital number, since it uses as much as digits as its factorization.

208218133 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2304, while the sum is 28.

The square root of 208218133 is about 14429.7655213105. The cubic root of 208218133 is about 592.7062625233.

The spelling of 208218133 in words is "two hundred eight million, two hundred eighteen thousand, one hundred thirty-three".