209353921942368 has 288 divisors, whose sum is σ = 649700688480480. Its totient is φ = 58844318883840.

The previous prime is 209353921942309. The next prime is 209353921942379. The reversal of 209353921942368 is 863249129353902.

It is a super-2 number, since 2×209353921942368² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 209353921942299 and 209353921942308.

It is a congruent number.

It is an unprimeable number.

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 in 47 ways as a sum of consecutive naturals, for example, 132795858 + ... + 134363118.

It is an arithmetic number, because the mean of its divisors is an integer number (2255905168335).

Almost surely, 2^{209353921942368} is an apocalyptic number.

209353921942368 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 209353921942368, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (324850344240240).

209353921942368 is an abundant number, since it is smaller than the sum of its proper divisors (440346766538112).

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

209353921942368 is a wasteful number, since it uses less digits than its factorization.

209353921942368 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1567750 (or 1567735 counting only the distinct ones).

The product of its (nonzero) digits is 151165440, while the sum is 66.

The spelling of 209353921942368 in words is "two hundred nine trillion, three hundred fifty-three billion, nine hundred twenty-one million, nine hundred forty-two thousand, three hundred sixty-eight".