209728834858368 has 768 divisors, whose sum is σ = 739801848600000. Its totient is φ = 58280149057536.

The previous prime is 209728834858349. The next prime is 209728834858399. The reversal of 209728834858368 is 863858438827902.

209728834858368 is a `hidden beast` number, since 2 + 0 + 9 + 7 + 28 + 8 + 3 + 4 + 8 + 583 + 6 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 21735805608 + ... + 21735815256.

Almost surely, 2^{209728834858368} is an apocalyptic number.

209728834858368 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 209728834858368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (369900924300000).

209728834858368 is an abundant number, since it is smaller than the sum of its proper divisors (530073013741632).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

209728834858368 is a wasteful number, since it uses less digits than its factorization.

209728834858368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13192 (or 13167 counting only the distinct ones).

The product of its (nonzero) digits is 8918138880, while the sum is 81.

The spelling of 209728834858368 in words is "two hundred nine trillion, seven hundred twenty-eight billion, eight hundred thirty-four million, eight hundred fifty-eight thousand, three hundred sixty-eight".