20121111210120 has 256 divisors, whose sum is σ = 62209674362880. Its totient is φ = 5203336320000.

The previous prime is 20121111210103. The next prime is 20121111210217. The reversal of 20121111210120 is 2101211112102.

It is a happy number.

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 20121111210120.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1719600270 + ... + 1719611970.

It is an arithmetic number, because the mean of its divisors is an integer number (243006540480).

Almost surely, 2^{20121111210120} is an apocalyptic number.

20121111210120 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 20121111210120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31104837181440).

20121111210120 is an abundant number, since it is smaller than the sum of its proper divisors (42088563152760).

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

20121111210120 is a wasteful number, since it uses less digits than its factorization.

20121111210120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14116 (or 14112 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 20121111210120 its reverse (2101211112102), we get a palindrome (22222322322222).

The spelling of 20121111210120 in words is "twenty trillion, one hundred twenty-one billion, one hundred eleven million, two hundred ten thousand, one hundred twenty".