208953909 has 6 divisors (see below), whose sum is σ = 301822326. Its totient is φ = 139302600.

The previous prime is 208953893. The next prime is 208953929. The reversal of 208953909 is 909359802.

It can be written as a sum of positive squares in only one way, i.e., 197543025 + 11410884 = 14055^2 + 3378^2 .

It is not a de Polignac number, because 208953909 - 2⁴ = 208953893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (208953929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 11608542 + ... + 11608559.

It is an arithmetic number, because the mean of its divisors is an integer number (50303721).

Almost surely, 2^208953909 is an apocalyptic number.

It is an amenable number.

208953909 is a deficient number, since it is larger than the sum of its proper divisors (92868417).

208953909 is a wasteful number, since it uses less digits than its factorization.

208953909 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23217107 (or 23217104 counting only the distinct ones).

The product of its (nonzero) digits is 174960, while the sum is 45.

The square root of 208953909 is about 14455.2381163369. The cubic root of 208953909 is about 593.4035863104.

The spelling of 208953909 in words is "two hundred eight million, nine hundred fifty-three thousand, nine hundred nine".