8209121070720 has 256 divisors, whose sum is σ = 27019163520000. Its totient is φ = 2117815664640.

The previous prime is 8209121070719. The next prime is 8209121070721. The reversal of 8209121070720 is 270701219028.

It is an interprime number because it is at equal distance from previous prime (8209121070719) and next prime (8209121070721).

It is not an unprimeable number, because it can be changed into a prime (8209121070721) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 205264486 + ... + 205304474.

It is an arithmetic number, because the mean of its divisors is an integer number (105543607500).

Almost surely, 2^{8209121070720} is an apocalyptic number.

8209121070720 is a gapful number since it is divisible by the number (80) 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 8209121070720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13509581760000).

8209121070720 is an abundant number, since it is smaller than the sum of its proper divisors (18810042449280).

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

8209121070720 is a wasteful number, since it uses less digits than its factorization.

8209121070720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43491 (or 43479 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 39.

Adding to 8209121070720 its reverse (270701219028), we get a palindrome (8479822289748).

The spelling of 8209121070720 in words is "eight trillion, two hundred nine billion, one hundred twenty-one million, seventy thousand, seven hundred twenty".