20011120121220 has 144 divisors (see below), whose sum is σ = 57375208501632. Its totient is φ = 5211224847360.

The previous prime is 20011120121207. The next prime is 20011120121227. The reversal of 20011120121220 is 2212102111002.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 20011120121220.

It is not an unprimeable number, because it can be changed into a prime (20011120121227) 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, 740289105 + ... + 740316135.

It is an arithmetic number, because the mean of its divisors is an integer number (398438947928).

Almost surely, 2^{20011120121220} is an apocalyptic number.

20011120121220 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 20011120121220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28687604250816).

20011120121220 is an abundant number, since it is smaller than the sum of its proper divisors (37364088380412).

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

20011120121220 is a wasteful number, since it uses less digits than its factorization.

20011120121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33802 (or 33757 counting only the distinct ones).

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

Adding to 20011120121220 its reverse (2212102111002), we get a palindrome (22223222232222).

The spelling of 20011120121220 in words is "twenty trillion, eleven billion, one hundred twenty million, one hundred twenty-one thousand, two hundred twenty".