21011102122220 has 384 divisors, whose sum is σ = 55330423529472. Its totient is φ = 6538110566400.

The previous prime is 21011102122217. The next prime is 21011102122277. The reversal of 21011102122220 is 2222120111012.

It is a super-3 number, since 3×21011102122220³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (17).

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 127 ways as a sum of consecutive naturals, for example, 6342015284 + ... + 6342018596.

It is an arithmetic number, because the mean of its divisors is an integer number (144089644608).

Almost surely, 2^{21011102122220} is an apocalyptic number.

21011102122220 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 21011102122220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27665211764736).

21011102122220 is an abundant number, since it is smaller than the sum of its proper divisors (34319321407252).

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

21011102122220 is a wasteful number, since it uses less digits than its factorization.

21011102122220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4121 (or 4119 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 21011102122220 its reverse (2222120111012), we get a palindrome (23233222233232).

The spelling of 21011102122220 in words is "twenty-one trillion, eleven billion, one hundred two million, one hundred twenty-two thousand, two hundred twenty".