20121121100220 has 96 divisors (see below), whose sum is σ = 64432334131200. Its totient is φ = 4595917208064.

The previous prime is 20121121100207. The next prime is 20121121100221. The reversal of 20121121100220 is 2200112112102.

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 20121121100220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121121100221) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 16041705 + ... + 17250464.

It is an arithmetic number, because the mean of its divisors is an integer number (671170147200).

Almost surely, 2^{20121121100220} is an apocalyptic number.

20121121100220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121121100220 is an abundant number, since it is smaller than the sum of its proper divisors (44311213030980).

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

20121121100220 is a wasteful number, since it uses less digits than its factorization.

20121121100220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33293627 (or 33293625 counting only the distinct ones).

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

Adding to 20121121100220 its reverse (2200112112102), we get a palindrome (22321233212322).

The spelling of 20121121100220 in words is "twenty trillion, one hundred twenty-one billion, one hundred twenty-one million, one hundred thousand, two hundred twenty".