208019197 has 4 divisors (see below), whose sum is σ = 209927740. Its totient is φ = 206110656.

The previous prime is 208019183. The next prime is 208019221. The reversal of 208019197 is 791910802.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 101082916 + 106936281 = 10054^2 + 10341^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-208019197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208019897) 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 in 3 ways as a sum of consecutive naturals, for example, 954108 + ... + 954325.

It is an arithmetic number, because the mean of its divisors is an integer number (52481935).

Almost surely, 2^208019197 is an apocalyptic number.

It is an amenable number.

208019197 is a deficient number, since it is larger than the sum of its proper divisors (1908543).

208019197 is a wasteful number, since it uses less digits than its factorization.

208019197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1908542.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 208019197 is about 14422.8706227297. The cubic root of 208019197 is about 592.5174410172.

Adding to 208019197 its reverse (791910802), we get a palindrome (999929999).

The spelling of 208019197 in words is "two hundred eight million, nineteen thousand, one hundred ninety-seven".