209368903808 has 16 divisors (see below), whose sum is σ = 417102113310. Its totient is φ = 104684451840.

The previous prime is 209368903801. The next prime is 209368903811. The reversal of 209368903808 is 808309863902.

209368903808 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 171667691584 + 37701212224 = 414328^2 + 194168^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is not an unprimeable number, because it can be changed into a prime (209368903801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 817847153 + ... + 817847408.

Almost surely, 2^209368903808 is an apocalyptic number.

It is an amenable number.

209368903808 is a deficient number, since it is larger than the sum of its proper divisors (207733209502).

209368903808 is an equidigital number, since it uses as much as digits as its factorization.

209368903808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1635694575 (or 1635694563 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 56.

The spelling of 209368903808 in words is "two hundred nine billion, three hundred sixty-eight million, nine hundred three thousand, eight hundred eight".