20021212101220 has 144 divisors (see below), whose sum is σ = 47820993454080. Its totient is φ = 7027458197760.

The previous prime is 20021212101161. The next prime is 20021212101227. The reversal of 20021212101220 is 2210121212002.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 20021212101194 and 20021212101203.

It is not an unprimeable number, because it can be changed into a prime (20021212101227) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 268260829 + ... + 268335451.

It is an arithmetic number, because the mean of its divisors is an integer number (332090232320).

Almost surely, 2^{20021212101220} is an apocalyptic number.

20021212101220 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 20021212101220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23910496727040).

20021212101220 is an abundant number, since it is smaller than the sum of its proper divisors (27799781352860).

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

20021212101220 is a wasteful number, since it uses less digits than its factorization.

20021212101220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78506 (or 78493 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 20021212101220 its reverse (2210121212002), we get a palindrome (22231333313222).

The spelling of 20021212101220 in words is "twenty trillion, twenty-one billion, two hundred twelve million, one hundred one thousand, two hundred twenty".