208109101 has 2 divisors, whose sum is σ = 208109102. Its totient is φ = 208109100.

The previous prime is 208109093. The next prime is 208109113. The reversal of 208109101 is 101901802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 157000900 + 51108201 = 12530^2 + 7149^2 .

It is a cyclic number.

It is not a de Polignac number, because 208109101 - 2³ = 208109093 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (208109171) 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, 104054550 + 104054551.

It is an arithmetic number, because the mean of its divisors is an integer number (104054551).

Almost surely, 2^208109101 is an apocalyptic number.

It is an amenable number.

208109101 is a deficient number, since it is larger than the sum of its proper divisors (1).

208109101 is an equidigital number, since it uses as much as digits as its factorization.

208109101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 22.

The square root of 208109101 is about 14425.9870026283. The cubic root of 208109101 is about 592.6027889345.

The spelling of 208109101 in words is "two hundred eight million, one hundred nine thousand, one hundred one".