21100220121012 has 48 divisors (see below), whose sum is σ = 49365171273600. Its totient is φ = 7014649578880.

The previous prime is 21100220120999. The next prime is 21100220121017. The reversal of 21100220121012 is 21012102200112.

It is a junction number, because it is equal to n+sod(n) for n = 21100220120982 and 21100220121000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100220121017) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 49412914 + ... + 49838102.

It is an arithmetic number, because the mean of its divisors is an integer number (1028441068200).

Almost surely, 2^{21100220121012} is an apocalyptic number.

It is an amenable number.

21100220121012 is an abundant number, since it is smaller than the sum of its proper divisors (28264951152588).

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

21100220121012 is a wasteful number, since it uses less digits than its factorization.

21100220121012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 436216 (or 436214 counting only the distinct ones).

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

Adding to 21100220121012 its reverse (21012102200112), we get a palindrome (42112322321124).

The spelling of 21100220121012 in words is "twenty-one trillion, one hundred billion, two hundred twenty million, one hundred twenty-one thousand, twelve".