9991288810000 has 225 divisors, whose sum is σ = 24582589677459. Its totient is φ = 3932665344000.

The previous prime is 9991288809989. The next prime is 9991288810001. The reversal of 9991288810000 is 188821999.

The square root of 9991288810000 is 3160900.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 22 ways, for example, as 6236747033104 + 3754541776896 = 2497348^2 + 1937664^2 .

It is a super-2 number, since 2×9991288810000² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (9991288810001) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 23074569784 + ... + 23074570216.

Almost surely, 2^{9991288810000} is an apocalyptic number.

9991288810000 is the 3160900-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 9991288810000

9991288810000 is an abundant number, since it is smaller than the sum of its proper divisors (14591300867459).

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

9991288810000 is an frugal number, since it uses more digits than its factorization.

9991288810000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1040 (or 513 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 55.

The spelling of 9991288810000 in words is "nine trillion, nine hundred ninety-one billion, two hundred eighty-eight million, eight hundred ten thousand".