21210110021100 has 1152 divisors, whose sum is σ = 83501407567872. Its totient is φ = 4014016819200.

The previous prime is 21210110021099. The next prime is 21210110021131. The reversal of 21210110021100 is 112001101212.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 8900590509 + ... + 8900592891.

It is an arithmetic number, because the mean of its divisors is an integer number (72483860736).

Almost surely, 2^{21210110021100} is an apocalyptic number.

21210110021100 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 21210110021100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41750703783936).

21210110021100 is an abundant number, since it is smaller than the sum of its proper divisors (62291297546772).

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

21210110021100 is a wasteful number, since it uses less digits than its factorization.

21210110021100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2815 (or 2808 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 12.

Adding to 21210110021100 its reverse (112001101212), we get a palindrome (21322111122312).

It can be divided in two parts, 212101 and 10021100, that added together give a palindrome (10233201).

The spelling of 21210110021100 in words is "twenty-one trillion, two hundred ten billion, one hundred ten million, twenty-one thousand, one hundred".