208912817 has 2 divisors, whose sum is σ = 208912818. Its totient is φ = 208912816.

The previous prime is 208912811. The next prime is 208912819. The reversal of 208912817 is 718219802.

208912817 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 207475216 + 1437601 = 14404^2 + 1199^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208912817 is a prime.

Together with 208912819, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (208912811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 104456408 + 104456409.

It is an arithmetic number, because the mean of its divisors is an integer number (104456409).

Almost surely, 2^208912817 is an apocalyptic number.

It is an amenable number.

208912817 is a deficient number, since it is larger than the sum of its proper divisors (1).

208912817 is an equidigital number, since it uses as much as digits as its factorization.

208912817 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 208912817 is about 14453.8166931783. The cubic root of 208912817 is about 593.3646850061.

The spelling of 208912817 in words is "two hundred eight million, nine hundred twelve thousand, eight hundred seventeen".