21212110101200 has 120 divisors (see below), whose sum is σ = 51657907670400. Its totient is φ = 8369207009280.

The previous prime is 21212110101199. The next prime is 21212110101289. The reversal of 21212110101200 is 210101121212.

It is a super-3 number, since 3×21212110101200³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31871024 + ... + 32529776.

It is an arithmetic number, because the mean of its divisors is an integer number (430482563920).

Almost surely, 2^{21212110101200} is an apocalyptic number.

21212110101200 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 21212110101200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25828953835200).

21212110101200 is an abundant number, since it is smaller than the sum of its proper divisors (30445797569200).

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

21212110101200 is a wasteful number, since it uses less digits than its factorization.

21212110101200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 659869 (or 659858 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21212110101200 its reverse (210101121212), we get a palindrome (21422211222412).

The spelling of 21212110101200 in words is "twenty-one trillion, two hundred twelve billion, one hundred ten million, one hundred one thousand, two hundred".