21001100122212 has 192 divisors, whose sum is σ = 58620836757504. Its totient is φ = 5725310791680.

The previous prime is 21001100122199. The next prime is 21001100122231. The reversal of 21001100122212 is 21222100110012.

It is a junction number, because it is equal to n+sod(n) for n = 21001100122191 and 21001100122200.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 629758123 + ... + 629791469.

It is an arithmetic number, because the mean of its divisors is an integer number (305316858112).

Almost surely, 2^{21001100122212} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21001100122212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29310418378752).

21001100122212 is an abundant number, since it is smaller than the sum of its proper divisors (37619736635292).

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

21001100122212 is a wasteful number, since it uses less digits than its factorization.

21001100122212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36778 (or 36776 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21001100122212 its reverse (21222100110012), we get a palindrome (42223200232224).

The spelling of 21001100122212 in words is "twenty-one trillion, one billion, one hundred million, one hundred twenty-two thousand, two hundred twelve".