2121121320120 has 384 divisors, whose sum is σ = 8071809071040. Its totient is φ = 477332766720.

The previous prime is 2121121320079. The next prime is 2121121320127. The reversal of 2121121320120 is 210231211212.

2121121320120 is a `hidden beast` number, since 21 + 211 + 213 + 201 + 20 = 666.

It is a super-2 number, since 2×2121121320120² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 2121121320093 and 2121121320102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121121320127) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4698552 + ... + 5130168.

Almost surely, 2^{2121121320120} is an apocalyptic number.

2121121320120 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 2121121320120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (4035904535520).

2121121320120 is an abundant number, since it is smaller than the sum of its proper divisors (5950687750920).

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

2121121320120 is a wasteful number, since it uses less digits than its factorization.

2121121320120 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431735 (or 431728 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 18.

Adding to 2121121320120 its reverse (210231211212), we get a palindrome (2331352531332).

The spelling of 2121121320120 in words is "two trillion, one hundred twenty-one billion, one hundred twenty-one million, three hundred twenty thousand, one hundred twenty".