21001122000000 has 336 divisors, whose sum is σ = 75540243033450. Its totient is φ = 5600294400000.

The previous prime is 21001121999989. The next prime is 21001122000049. The reversal of 21001122000000 is 22110012.

It can be written as a sum of positive squares in 7 ways, for example, as 7782894766656 + 13218227233344 = 2789784^2 + 3635688^2 .

It is a super-3 number, since 3×21001122000000³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (9).

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 41 ways as a sum of consecutive naturals, for example, 17416636 + ... + 18583364.

Almost surely, 2^{21001122000000} is an apocalyptic number.

21001122000000 is a gapful number since it is divisible by the number (20) 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 21001122000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37770121516725).

21001122000000 is an abundant number, since it is smaller than the sum of its proper divisors (54539121033450).

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

21001122000000 is an frugal number, since it uses more digits than its factorization.

21001122000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1166779 (or 1166739 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 21001122000000 its reverse (22110012), we get a palindrome (21001144110012).

The spelling of 21001122000000 in words is "twenty-one trillion, one billion, one hundred twenty-two million", and thus it is an aban number.