208171289 has 2 divisors, whose sum is σ = 208171290. Its totient is φ = 208171288.

The previous prime is 208171247. The next prime is 208171297. The reversal of 208171289 is 982171802.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 151093264 + 57078025 = 12292^2 + 7555^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208171289 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (208171489) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104085644 + 104085645.

It is an arithmetic number, because the mean of its divisors is an integer number (104085645).

Almost surely, 2^208171289 is an apocalyptic number.

It is an amenable number.

208171289 is a deficient number, since it is larger than the sum of its proper divisors (1).

208171289 is an equidigital number, since it uses as much as digits as its factorization.

208171289 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16128, while the sum is 38.

The square root of 208171289 is about 14428.1422574079. The cubic root of 208171289 is about 592.6618110401.

The spelling of 208171289 in words is "two hundred eight million, one hundred seventy-one thousand, two hundred eighty-nine".